By the end of month four a baby typically:

• May sleep about six hours at night before waking (total sleep typically 14 to 17 hours)
• Rolls over (usually stomach to back is first)
• Sits with support
• Lifts head up 90 degrees
• Can follow a moving object for a 180-degree arc
• Babbles and amuses self with new noises
• Responds to all colors and shades
• Explores objects with his mouth
• Recognizes a bottle or breast
• Communicates pain, fear, loneliness and discomfort through crying
• Responds to a rattle or bell

By the end of month five a baby typically:

• Pays attention to small objects
• Experiments with the concept of cause and effect
• Can see across the room
• Begins to use hands in a raking fashion to bring toys near
• Begins teething process

By the end of month six a baby typically:

• Keeps head level when pulled to sitting position
• Makes some vowel-consonant sounds
• Sits by self with minimal support
• Opens mouth for spoon
• Reaches for and grabs objects
• Rolls over and back
• Drinks from a cup with help
• Can hold bottle
• Copies some facial expressions
• Makes two-syllable sounds

By the end of month seven a baby typically:

• Can self-feed some finger foods
• Makes wet razzing sounds
• Turns in the direction of a voice
• Plays peekaboo
• Imitates many sounds
• Distinguishes emotions by tone of voice