Baby development at 4-5 months is the stage when babies are becoming more active, social, and curious about their surroundings.

They begin to smile and laugh more, make sounds, and explore by reaching for and mouthing objects. Parents can support their baby’s development by playing together—singing, reading, doing tummy time, and making funny faces. Talking, listening, and responding to your baby’s sounds helps build early communication skills.

See below PDF from Raising Children’s Network around what you can do to help your child’s development