Under the things that most babies will probably be able to, Emma can smile in response to a smile, notice her hands, respond to a loud sound in some way. She can't grasp and shake hand toys yet
She can do all of the things that half of all babies will be able to: vocalize in ways other than crying and lifting her head 45 degrees when on her tummy.
Under the things that some babies will be able to do, she can hold her head steady when upright, roll over (tummy to back), pay attention to objects as small as a raisin, reach for dangling objects, she can't raise her chest supported by her arms yet.
Under the things that a few babies will be able to do, Emma can lift her head 90 degrees while on her tummy, bring both hands together, smile spontaneously, follow an object held about 6 inches above her face and moved 180 degrees watching all the way. She can't laugh out loud or squeal in delight yet.
