Things Nobody Tells You About Your Baby

Ten common beliefs about babies and toddlers, what the research actually says, and what is going on in the brain. Tap a card to read more.

Illustration of a sleeping newborn with a glowing brain and glowing nerve connections around the head

Ten things worth knowing

Thing 1 · newborn and babyYour baby's cry is information, not a lesson to ignoreCommon belief: "Let your baby cry so they learn."Tap to read the scienceHide

What research indicates

Crying is a baby's main way of signalling needs. In colic, no single cause has been found. Babies cry about two hours a day on average in the first six weeks, easing to about an hour by 10 to 12 weeks, with big differences between babies. The small amount of recent research on sleep training does not show harm to attachment, but the studies are small and short, they cannot rule out every effect, and this is not advice to leave a baby crying. Gentler, responsive approaches also exist, and choosing not to sleep-train is a legitimate choice.

What is happening in the brain

A young baby's prefrontal cortex and calming systems are still maturing, so a baby cannot settle by themselves the way an older child can. Caregivers help their baby's body and feelings settle, a process called co-regulation. Regulation changes with age: in one study, babies from 5 to 18 months relied more on shared regulation as they grew.

Try this: Check the basics (hunger, diaper, temperature, gas), then try holding, walking, or gentle rocking. If crying is very prolonged, sounds different, or comes with poor feeding, call your baby's health professional. A fever of 100.4°F (38°C) or higher in a baby under 3 months needs medical care right away.

Evidence Wolke et al., 2017 DOI; Zeevenhooven et al., 2018 DOI; Gradisar et al., 2016 DOI; Bilgin & Wolke, 2020 DOI; Reuter et al., 2020 DOI; Kolk & Rakic, 2022 DOI; Atkinson et al., 2021 DOI

Thing 2 · newborn and babyYour baby is not trying to manipulate youCommon belief: "They're just crying to get picked up."Tap to read the scienceHide

What research indicates

We did not find research showing that young babies cry to manipulate. Research describes crying as a signal. Sensitive, responsive care is associated with slightly better child outcomes, and we found no evidence that comforting babies "spoils" them.

What is happening in the brain

Planning and understanding other minds develop gradually over the first years, alongside brain regions that are still maturing. A newborn's cry is better understood as a signal of a felt need, such as discomfort, hunger, or wanting closeness.

Try this: If your baby wants to be held, holding is a reasonable response. You can also put them down when you need to. Responding does not have to be instant every time.

Evidence Cooke et al., 2022 DOI; Britto et al., 2017 DOI; Vreden et al., 2025 DOI; Kolk & Rakic, 2022 DOI

Thing 3 · toddlerYour toddler says "no" because they are growingCommon belief: "They're being defiant."Tap to read the scienceHide

What research indicates

Between about ages one and three, toddlers' words, preferences, and sense of self develop quickly, and saying "no" is part of this. Children say the word "no" early, but they understand it as a logical idea ("it is not in the box") only after about age two. Tantrums are common: in one survey of 861 children aged 1 to 5, tantrums were less frequent in older children but lasted longer (parent report, comparing different children by age). Parenting that takes the child's view, offers choices where possible, and explains rules is linked with better wellbeing, mostly in studies of older children. It is different from permissiveness.

What is happening in the brain

Executive function (planning, holding information in mind, stopping an impulse) develops gradually from infancy through the preschool years and beyond. A toddler wants things strongly while the brain parts that apply the brakes are still maturing.

Try this: Offer a limited choice ("blue cup or green cup?"), name the feeling ("you wanted to keep playing"), and hold the limit kindly. Tantrums that are severe, include harming themselves, or last a very long time are worth mentioning to your pediatrician.

Evidence Feiman et al., 2017 DOI; Van den Akker et al., 2022 DOI; Bradshaw et al., 2025 DOI; Hoyniak et al., 2023 DOI; Montroy et al., 2016 DOI

Thing 4 · newborn and babyYour baby depends on connectionCommon belief: "They'll be fine on their own."Tap to read the scienceHide

What research indicates

Human babies are born very dependent. In the first year they cannot move, feed, or regulate themselves without help from caregivers, and researchers see this long dependence as part of how babies learn from and bond with the people around them. Attachment is the lasting bond that grows between a baby and familiar caregivers; its purposes are protection and a felt sense of safety.

What is happening in the brain

Brain networks develop fastest in the first two years, shaped by genes and experience, including the sights, sounds, and touch of caregiving; parents are one important part of that environment, not all of it.

Try this: Share the work. Other consistent caregivers can be attachment figures too, so you do not have to be the only one.

Evidence Izaki et al., 2024 DOI; Burkart et al., 2025 DOI; Kliesch, 2025 DOI; Gilmore et al., 2018 DOI; Britto et al., 2017 DOI

Thing 5 · baby and toddlerComforting does not make them weakCommon belief: "If you always pick them up, they'll be clingy."Tap to read the scienceHide

What research indicates

We found no study showing that comforting or promptly responding to a baby or toddler makes a child more dependent. Long-term studies point the other way: mothers' sensitive parenting was associated with children's language, executive function, and self-reliance in a US cohort of 1,364 children, and more securely attached children were less likely to be overly reliant on their teachers. These are observational studies, not trials.

What is happening in the brain

Attachment theory's "secure base" idea is that children who can count on comfort can explore more freely. The evidence is still limited, so it is a theory with some supporting findings, not a proven rule.

Try this: Comfort when your child is upset, then encourage them back to play when they are ready.

Evidence Foley et al., 2025 DOI; Neuhaus et al., 2021 DOI; Verschueren & Spilt, 2021 DOI; Bernier et al., 2024 DOI; Nivison et al., 2026 DOI

Thing 6 · baby and toddlerYour baby cannot calm down like an adultCommon belief: "Just tell them to calm down."Tap to read the scienceHide

What research indicates

Babies depend on caregivers to help them regulate emotion, and regulation changes with age. In one study following infants from 5.5 to 18 months, babies used less self-soothing and more regulation shared with their caregiver as they grew older. Infants also differ a lot in how they regulate.

What is happening in the brain

The prefrontal cortex, which helps manage impulses and emotions, keeps maturing until about the third decade of life. Young children rely on adults to help them calm down because these systems are still under construction. That is normal development, not a failure of the child or the parent.

Try this: Lower the volume, move closer, speak softly, and wait. Carrying and a combination of swaddling, shushing, and jiggling reduced crying in small laboratory experiments, and skin-to-skin contact reduced crying after painful procedures in newborns. The evidence is modest. If you swaddle, do it only with the baby on their back, with the hips loose and no weighted swaddles, and stop when the baby shows signs of rolling.

Evidence Kolk & Rakic, 2022 DOI; Atkinson et al., 2021 DOI; Ohmura et al., 2022 DOI; Möller et al., 2019 DOI; Johnston et al., 2017 DOI; Pease et al., 2016 DOI

Thing 7 · for youYou are allowed to need a breakCommon belief: "A good mother never gets frustrated."Tap to read the scienceHide

What research indicates

Crying can be exhausting, and frustration is common. Needing a break is not a sign you will harm your baby. Stepping away and asking for help is widely recommended; research on whether it prevents injury is limited. If you feel overwhelmed and your baby is fed, changed, and safe, it is reasonable to place the baby on their back in a safe sleep space (firm, flat, no soft bedding), step away for a few minutes to calm yourself, and ask another adult to take over or call a health professional.

What is happening in the brain

Stress and sleep loss affect adults' brains and bodies too. Parents who are struggling, with depression, anxiety, very broken sleep, or little support, may find caregiving harder on average. The link with depression is small, and one large study found it largely explained by other circumstances. Many such parents care well.

Never shake a baby. Shaking can cause serious brain injury or death. If you feel you might lose control, put your baby down safely and step away. If a baby has been shaken, or is limp, very hard to wake, or not breathing normally, call 911 (or your local emergency number) right away. Do not wait for visible injury, and ask someone nearby to help.
Try this: Line up a "tag-out" person before you need one. Postpartum Support International's free HelpLine is 1-800-944-4773 (the HelpLine is not a crisis line; for a crisis call or text the National Maternal Mental Health Hotline at 1-833-852-6262, or call 988, the Suicide and Crisis Lifeline).

Evidence Moon et al., 2022 DOI; Scott et al., 2022 DOI; Chang et al., 2024 DOI; Bernard et al., 2018 DOI; MacMillan et al., 2021 DOI; Padrutt et al., 2026 DOI

Thing 8 · for youYou do not have to be a perfect motherCommon belief: "One mistake and the bond is broken."Tap to read the scienceHide

What research indicates

Parent and baby are not in perfect step. In one study of 116 mother-infant pairs, the pair was in a matched positive state about 58 to 70 percent of the time in play, and mismatches typically lasted about five seconds before they matched again. Out of sync is normal; repair is part of ordinary life. In a large review, sensitive care explained only a modest share of differences in attachment, and no parent is sensitive all the time.

What is happening in the brain

Brains stay changeable, and the research we found concerns repeated experience over time rather than single moments. We found no research showing that ordinary parenting stress or an imperfect day changes a child's brain.

Try this: After a rough moment, repair: a smile, a cuddle, a few calm words. Then let it go.

Evidence Hu et al., 2025 DOI; Madigan et al., 2024 DOI; Nivison et al., 2026 DOI; Nelson & Gabard-Durnam, 2020 DOI; Reh et al., 2020 DOI

Thing 9 · for youYour childhood does not have to become your child'sCommon belief: "I will repeat what happened to me."Tap to read the scienceHide

What research indicates

Parents' early attachment experiences are linked with their children's attachment only moderately (about r = .29 to .31), and the link has weakened in newer studies. Most differences between children are not explained by a parent's history. Programs that help parents notice and respond to their baby's signals can increase children's security.

What is happening in the brain

The brain stays able to change throughout life, though change is usually greatest early. After severe early adversity, stable high-quality care was linked with better outcomes in one trial. That does not mean everyone can "heal completely".

Try this: Reflect on what you want to keep and what you want to change, and find support. See "Before you become a mother" on the secure attachment page.

Evidence Verhage et al., 2016 DOI; Verhage et al., 2018 DOI; Mountain et al., 2017 DOI; King et al., 2023 DOI; Reh et al., 2020 DOI

Thing 10 · baby and familyYour baby can feel safe with more than one personCommon belief: "Only the mother can really comfort a baby."Tap to read the scienceHide

What research indicates

Babies usually form attachments to more than one caregiver. Fathers' sensitivity relates to security about as strongly as mothers', and children's security with fathers is, on average, only very slightly lower than with mothers. In one hunter-gatherer community, caregivers other than the mother provided 40 to 50 percent of a child's care. Evidence on other caregivers such as grandparents and adoptive parents is more limited.

What is happening in the brain

Researchers argue that sharing care among several adults has long been part of how human babies are raised.

Try this: Invite a partner, grandparent, or trusted caregiver to share feeds, bedtime, or soothing, so you can rest too.

Evidence Madigan et al., 2024 DOI; Pinquart, 2022 DOI; Chaudhary et al., 2024 DOI; Burkart et al., 2025 DOI

Illustration of six baby faces with common reasons for crying: hunger (rooting, sucking movements), tiredness (rubbing eyes, beginning to fuss), discomfort (diaper, temperature, clothing), overstimulation (turns away, fussy, needs a calmer environment), pain or illness (persistent crying may have other signs), and need for closeness (seeks comfort and connection).
A baby's communication through crying. Common cues, not a decoder. Many crying spells have no cause that anyone can find, and babies differ, so use this as a starting point for checking the basics and then comforting. Call your baby's health professional if crying is very prolonged, sounds different, or comes with poor feeding or fever. The labels inside the picture are in English.

What is my baby trying to tell me?

Four everyday situations. Tap an option to read what research suggests. These are possibilities to think about, not diagnoses, and no single answer is right for every child.

A. Your six-week-old is crying

It is evening, your baby has been fed and changed, and they are crying hard.

B. Your toddler says "NO!"

You ask your two-year-old to put on their shoes. They say "no" and sit down on the floor.

C. You feel overwhelmed

It has been a long night. Your baby is fed, changed, and still crying, and you feel your temper rising.

D. Your baby is upset when you leave

You step out of the room and your ten-month-old cries and reaches for the door.

What is still uncertain

  • Most of these findings are associations from observational studies; they cannot prove that a parenting choice causes an outcome.
  • Sleep-training studies are small and short, so we cannot say every method is safe for every baby.
  • We found no recent studies tracking the timing of separation distress (ages come from milestone checklists), and no randomized trials of "spoiling" or of whether comforting changes later dependence.
  • Many studies come from a limited range of countries, so we know less about families elsewhere. Families everywhere comfort and raise babies in many good ways.
  • This content has not yet been reviewed by a pediatrician or developmental specialist.
Psychoeducation, not medical advice. Research describes averages across many families. It cannot tell you what is right for your own baby. Each card names its evidence at the bottom, with a link to the original article. Full references are at the end of the page.

The message under every card

Babies need connection, protection, and responsive care. Crying is communication. Saying "no" is normal growth. Calm develops slowly, over years. And you do not have to do this alone. Secure attachment is not created by a mother sacrificing her own wellbeing. Your rest, health, and support are part of caring for your baby, and they belong in the picture just as much as the neuroscience.

Support for mothers after birth: Postpartum Support International

Postpartum Support International (PSI) offers free help for pregnancy and postpartum mental health, for mothers and for other parents. You do not need to be in crisis to reach out. Feeling overwhelmed, anxious, sad, or not like yourself after a baby is common and treatable, and you will always hear back from a person, not an AI program.

  • Call the PSI HelpLine: 1-800-944-4773 (press 1 for Spanish, 2 for English)
  • Text in English: text "Help" to 800-944-4773
  • Text in Spanish: 971-203-7773
  • App: download "Connect by PSI" in your app store

The HelpLine is free and confidential. You can leave a message any time, and calls and texts are returned every day, from 8 am to 11 pm Eastern time. It gives information, support, and local resources. It is not a crisis line and does not handle emergencies. About the HelpLine

In a crisis or emergency, reach out right now. The National Maternal Mental Health Hotline is free, available 24/7 in the United States, and you can call or text 1-833-852-6262. You can also call or text 988, text HOME to 741741, or call 911 if you or your baby are in immediate danger. PSI emergency information

References

All sources are peer-reviewed journal articles or professional policy statements published 2016 to 2026. Select a number to jump to its reference, and a DOI to open the original article. APA 7th edition.

  1. Wolke, D., Bilgin, A., & Samara, M. (2017). Systematic review and meta-analysis: Fussing and crying durations and prevalence of colic in infants. The Journal of Pediatrics, 185, 55-61.e4. https://doi.org/10.1016/j.jpeds.2017.02.020 https://doi.org/10.1016/j.jpeds.2017.02.020 meta-analysis
  2. Zeevenhooven, J., Browne, P. D., L'Hoir, M. P., de Weerth, C., & Benninga, M. A. (2018). Infant colic: mechanisms and management. Nature Reviews Gastroenterology & Hepatology, 15(8), 479-496. https://doi.org/10.1038/s41575-018-0008-7 https://doi.org/10.1038/s41575-018-0008-7 narrative review
  3. Gradisar, M., Jackson, K., Spurrier, N. J., Gibson, J., Whitham, J., Williams, A. S., Dolby, R., & Kennaway, D. J. (2016). Behavioral interventions for infant sleep problems: A randomized controlled trial. Pediatrics, 137(6), e20151486. https://doi.org/10.1542/peds.2015-1486 https://doi.org/10.1542/peds.2015-1486 RCT
  4. Bilgin, A., & Wolke, D. (2020). Parental use of 'cry it out' in infants: No adverse effects on attachment and behavioural development at 18 months. Journal of Child Psychology and Psychiatry, 61(11), 1184-1193. https://doi.org/10.1111/jcpp.13223 https://doi.org/10.1111/jcpp.13223 longitudinal cohort
  5. Reuter, A., Silfverdal, S.-A., Lindblom, K., & Hjern, A. (2020). A systematic review of prevention and treatment of infant behavioural sleep problems. Acta Paediatrica, 109(9), 1717-1732. https://doi.org/10.1111/apa.15182 https://doi.org/10.1111/apa.15182 systematic review
  6. Kolk, S. M., & Rakic, P. (2022). Development of prefrontal cortex. Neuropsychopharmacology, 47(1), 41-57. https://doi.org/10.1038/s41386-021-01137-9 https://doi.org/10.1038/s41386-021-01137-9 narrative review (human and animal)
  7. Atkinson, N. H., Jean, A. D. L., & Stack, D. M. (2021). Emotion regulation from infancy to toddlerhood: Individual and group trajectories of full-term and very-low-birthweight preterm infants. Infancy, 26(4), 570-595. https://doi.org/10.1111/infa.12405 https://doi.org/10.1111/infa.12405 longitudinal observational cohort
  8. Cooke, J. E., Deneault, A.-A., Devereux, C., Eirich, R., Fearon, R. M. P., & Madigan, S. (2022). Parental sensitivity and child behavioral problems: A meta-analytic review. Child Development, 93(5), 1231-1248. https://doi.org/10.1111/cdev.13764 https://doi.org/10.1111/cdev.13764 meta-analysis
  9. Britto, P. R., Lye, S. J., Proulx, K., Yousafzai, A. K., Matthews, S. G., Vaivada, T., Perez-Escamilla, R., Rao, N., Ip, P., Fernald, L. C. H., MacMillan, H., Hanson, M., Wachs, T. D., Yao, H., Yoshikawa, H., Cerezo, A., Leckman, J. F., & Bhutta, Z. A. (2017). Nurturing care: promoting early childhood development. The Lancet, 389(10064), 91–102. https://doi.org/10.1016/s0140-6736(16)31390-3 https://doi.org/10.1016/s0140-6736(16)31390-3 narrative review (Lancet Series paper)
  10. Vreden, C., Atim, S., Buryn-Weitzel, J. C., Di Gregorio, G., Donnellan, E., Hoffman, M., Holden, E., Jurua, M., Knapper, C. V., Marshall, S., Paricia, J., Tusiime, F., Wilke, C., Slocombe, K. E., & Clay, Z. (2025). Maternal responsiveness to infant distress: A cross-cultural investigation in Uganda and the United Kingdom. Developmental Psychology. https://doi.org/10.1037/dev0002038 https://doi.org/10.1037/dev0002038 longitudinal cohort (naturalistic observation)
  11. Feiman, R., Mody, S., Sanborn, S., & Carey, S. (2017). What Do You Mean, No? Toddlers’ Comprehension of Logical “No” and “Not”. Language Learning and Development, 13(4), 430-450. https://doi.org/10.1080/15475441.2017.1317253 https://doi.org/10.1080/15475441.2017.1317253 experimental comprehension study (3 experiments)
  12. Van den Akker, A. L., Hoffenaar, P., & Overbeek, G. (2022). Temper Tantrums in Toddlers and Preschoolers: Longitudinal Associations with Adjustment Problems. Journal of Developmental & Behavioral Pediatrics, 43(7), 409-417. https://doi.org/10.1097/dbp.0000000000001071 https://doi.org/10.1097/dbp.0000000000001071 cross-sectional survey plus 1-year follow-up (subsample)
  13. Bradshaw, E. L., Duineveld, J. J., Conigrave, J. H., Steward, B. A., Ferber, K. A., Joussemet, M., Parker, P. D., & Ryan, R. M. (2025). Disentangling autonomy-supportive and psychologically controlling parenting: A meta-analysis of self-determination theory’s dual process model across cultures. American Psychologist, 80(6), 879-895. https://doi.org/10.1037/amp0001389 https://doi.org/10.1037/amp0001389 meta-analysis (meta-analytic structural equation modelling)
  14. Hoyniak, C. P., Donohue, M. R., Quiñones-Camacho, L. E., Vogel, A. C., Perino, M. T., Hennefield, L., Tillman, R., Barch, D. M., & Luby, J. L. (2023). Developmental pathways from preschool temper tantrums to later psychopathology. Development and Psychopathology, 35(4), 1643-1655. https://doi.org/10.1017/s0954579422000359 https://doi.org/10.1017/s0954579422000359 prospective longitudinal cohort (enriched for early psychopathology)
  15. Montroy, J. J., Bowles, R. P., Skibbe, L. E., McClelland, M. M., & Morrison, F. J. (2016). The development of self-regulation across early childhood. Developmental Psychology, 52(11), 1744-1762. https://doi.org/10.1037/dev0000159 https://doi.org/10.1037/dev0000159 longitudinal cohort (3 samples)
  16. Izaki, A., Verbeke, W. J. M. I., Vrticka, P., & Ein-Dor, T. (2024). A narrative on the neurobiological roots of attachment-system functioning. Communications Psychology, 2(1), 96. https://doi.org/10.1038/s44271-024-00147-9 https://doi.org/10.1038/s44271-024-00147-9 narrative review (theoretical)
  17. Burkart, J. M., Cerrito, P., Natalucci, G., & van Schaik, C. P. (2025). Cooperative Breeding as a Likely Early Catalyst of Human Evolution. Evolutionary Anthropology: Issues, News, and Reviews, 34(3), e70016. https://doi.org/10.1002/evan.70016 https://doi.org/10.1002/evan.70016 review (evolutionary anthropology)
  18. Kliesch, C. (2025). Postnatal dependency as the foundation of social learning in humans. Proceedings of the Royal Society B: Biological Sciences, 292(2045), 20242818. https://doi.org/10.1098/rspb.2024.2818 https://doi.org/10.1098/rspb.2024.2818 theoretical review
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