In Ancient Egypt the lateral lock of hair was a distinctive of childhood.
For the ancient Egyptian artist of the Old Kingdom, the lateral lock of hair pending from the scalp was, joint with nudity, an iconographical resource applied mainly to boys. Many familiar statues from the Memphite cemetery show how the male was the one with that hairstyle.
Also the two dimensional art presents many images of young boys with the side lock of hair, as for instance in the reliefs from the tomb of Ptahhotep.
But, was this ancient Egyptian rule always like that? No.
The group statue of Nikare with his wife and his daughter is one good exception. This statue comes from Saqqara (?) and is dated in the V Dynasty. Nikare’s daughter is represented in an unusual way for the rules of Ancient Egypt.