1–3 Month Old Development: What to Expect

The first three months are a period of rapid growth and transition from the "fourth trimester" into early infancy. Your baby is beginning to interact more with their environment and with you.

Key Milestones

  • Social smiling (6-8 weeks)
  • Following moving objects with eyes
  • Pushing up on arms during tummy time
  • Opening and shutting hands

Is This Normal? Frequently Asked Questions

When will my baby first smile?

Most babies develop their first "social smile" — a smile in response to your face or voice — between 6 and 8 weeks. Before then, you may see reflexive smiles during sleep, but the social smile is a major milestone in emotional bonding.

Is it normal for my 2-month-old to cry more in the evening?

Yes. Many babies experience a "witching hour" or period of increased fussiness in the late afternoon or evening. This is often due to overstimulation or a developing nervous system. Soothing techniques like rhythmic rocking, swaddling, or a warm bath can help.