Social smile
What is this milestone?
Smiles in response to people or voices
The social smile is one of the most rewarding early milestones. Unlike the reflexive, 'gas-induced' smiles seen in the first few weeks, this is a genuine, intentional expression of happiness in response to seeing a face, hearing a voice, or feeling a gentle touch.
Why it matters
This milestone marks a significant leap in social and emotional development. It demonstrates that your baby is beginning to understand social reciprocity—the back-and-forth rhythm of communication—and is actively seeking connection with you and others.
What to expect leading up to it
Before this emerges, you might notice your baby studying your face more intently, making brief eye contact, or appearing to calm down when they hear your voice. These moments of focused attention are laying the groundwork for that first big grin.
How to encourage and support it
Get up close! Babies at this age focus best on objects 8-12 inches away. Talk, sing, and make exaggerated facial expressions. Respond enthusiastically when they do smile to reinforce that their actions have a positive, loving effect on the world.
When to talk to your doctor
The CDC's milestone checklists say what most children (75% or more) can do by each age. They list “Smiles when you talk to or smile at her” by 2 months. If your child is not doing this by then, the CDC's advice is not to wait: talk with your child's doctor, share your concerns, and ask about developmental screening. The same goes at any age if your child loses a skill they once had, or if anything else about their development worries you. Source: the CDC's “Learn the Signs. Act Early.” milestone checklists, checked October 5, 2026.
Every child develops at their own pace, and the ages here are the CDC's general guidance — not a developmental screening. This article is not medical advice and is not a substitute for your pediatrician. If you have any concern about your child's development, talk to them.
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