2-3 months
able to turn head up, can turn side to side. Makes cooing or gurgling noises and can turn head to sound
4-5 months
grasps, switch and roll over tummy to back, can babble and can mimic sounds
6-7 months
sits at 6 and waves bye-bye. Can recognize familiar faces and knows if someone is a stranger. Passes things back and forth between hands
8-9 months
Stands straight at 8, has favorite toy, plays peek-a-boo
10-11 months
belly to butt
12-13 months
12 and up, drinks from a cup. Cries when parents leave, uses furniture to cruise.