Children's size 12 is suitable for children with height 1 10cm. Clothes of this size are usually worn by children aged five or six. The size standard of 120 is suitable for children with a height of 120cm. Clothes of this size are usually worn by children aged seven or eight. When choosing a size, you need to combine the height of the child. If the child is taller, you can choose clothes of a larger size. At the same time, we should also pay attention to the growth and development of children and adjust the size of clothes in time to avoid being too tight or too loose.