Can’t wait to hear your baby laugh?

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How Do Infants Learn?https://publications.aap.org/patiented/article/doi/10.1542/peo_document355/81994/How-Do-Infants-LearnOpens a new window[Accessed November 2024]

CDC.

Milestone Moments.https://www.cdc.gov/ncbddd/actearly/pdf/booklets/Milestone-Moments-Booklet_Reader_508.pdfOpens a new window[Accessed November 2024]

CDC.

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Important Milestones: Your Baby By Two Months.https://www.cdc.gov/ncbddd/actearly/milestones/milestones-2mo.htmlOpens a new window[Accessed November 2024]

CDC.

Important Milestones: Your Baby By Four Months.https://www.cdc.gov/ncbddd/actearly/milestones/milestones-4mo.htmlOpens a new window[Accessed November 2024]

CDC.

Important Milestones: Your Baby By Six Months.https://www.cdc.gov/ncbddd/actearly/milestones/milestones-6mo.htmlOpens a new window[Accessed November 2024]

AAP.

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Checkup Checklist: 4 Months Old.https://www.healthychildren.org/English/ages-stages/Your-Childs-Checkups/Pages/Your-Checkup-Checklist-4-Months-Old.aspxOpens a new window[Accessed November 2024]

NIH.

A video polysomnographic study of spontaneous smiling during sleep in newborns.

National Institute of Health.https://pubmed.ncbi.nlm.nih.gov/32748500/Opens a new window[Accessed November 2024]

NIH.

smiling baby showing two teeth

Sleep physiology and sleep disorders in childhood.

National Institute of Health.https://pmc.ncbi.nlm.nih.gov/articles/PMC3630965/Opens a new window[Accessed November 2024]

AAP.

Mary Sauer is a freelance parenting and health writer living in Kansas City.

Pregnant mom and toddler

She is a mom of four and loves to hike with her kids, read, and knit.

Cooking a complicated meal her kids probably won’t eat is one of her favorite pastimes.

A father with a sleeping toddler on his lap

worried girl staring

phone with BabyCenter app

Mary Sauer