At first, babies can only hold their heads up for a max of a few seconds while on their stomachs. But by 3 months, babies lying on their stomachs can support not only their heads, but also their chests and arms. Arm and hand movement also advances fast during this stage. Now babies use an open hand for grabbing at objects. By the end of this period, most babies can support head and superior body when on stomach, kick and stretch legs while lying down, open and close hands, shake toys, and swipe at dangling objects
From 4-7 months, babies learn to coordinate their new visual abilities with new motor skills. Babies will examine toys by grasping them and placing them in their mouths. By age 6-8 months, they can move objects from one hand to the other and turn them from side to side. Babies will begin to push up using their arms and arch their back to elevate their chest. Most babies also rock while on their stomachs, kick their legs, and “swim” with their arms. By the end of this period, babies should be able to roll over from stomach to back and vice