1. Baby girl: height 58.6 ~ 72.1cm; Weight 5.33 ~10.38 kg; Head circumference is 38. 1~45.7cm. Baby boy: height is 59.9 ~ 73.9cm；. The weight is 5.66 ~11.15 kg.
2. Physiologically speaking, lower limbs: A child can bend and straighten his legs independently, so that when he keeps his feet upright, he will push down and straighten his legs. Little tricks: I can reach the toy I want to use with one hand, and I can also catch the toy, but the accuracy is not enough. I have to repeat an action several times.
3. Sit with your back straight; I always want to turn over when I wake up, and occasionally I can turn from my back to my side. When lying on the bed, I really want to climb forward; Lying on your back in bed, you can easily turn to prone position. It can distinguish the voices of family members and make consonants. You can learn to be funny and make a sound to interrupt the conversation of adults; When talking to him, he will not cry; Resist people who want to take his toys and repeat an action, such as often deliberately leaving things in their hands on the ground and picking them up and throwing them away.