Social & emotional
Social smile
Many babies — 1–3 months
Smiling back at you on purpose — the first real social connection.
What’s happening
A social smile — smiling back at you on purpose, not just reflexively — is usually the first sign your baby is engaging with you as a person, not just responding to sensation. It's different from the fleeting, often sleep-related smiles newborns show in the first weeks, which aren't yet social.
How to support it
- Get face-to-face during alert, calm moments — smiling back reinforces it, and babies love the exchange.
- Exaggerated expressions and a sing-song voice hold their attention better than a flat one at this age.
- Give it a moment — a baby often needs a beat to process your face and 'decide' to smile back; don't rush past it.
When to ask your pediatrician
Smiling when you talk to or smile at them is one of the CDC's checkpoints for 2 months. If your baby never smiles at you or seems uninterested in faces by then, mention it at their next visit.
Where this comes from
- From Baby to Big Kid: Month 4Zero to Three
- Milestones by 2 MonthsCDC
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