MASTERED SKILLS - At 4 months old, most babies can:
• Hold head steady when upright
• Sit in an upright position with support
• Can bear weight on his legs when supported
• Coo when you talk to him.

EMERGING SKILLS - may be able to:
• Start to roll over from front to back, but not able to roll from back to front
• Grasp a rattle or small toy
• Reach for an object.

ADVANCED – a few babies can:
• Imitate some simple sounds like da-da or ma-ma
• Sit without support.