Once a baby can sit, his world becomes larger as he can reach for objects. Developing core stability and then movement are key features of this age. Toys that move away from a child too easily can be frustrating initially but they are great for motivating a child to learn to move in order to follow and retrieve it. Bouncers and walkers are good for developing trunk and leg muscles. Teething is very common around this time so moulded plastic toys that can be chewed to bring relief to painful gums will also be popular.