>>177
I think they mainly do it to make them look cute. Older women don't usually have them, and men don't either. It's based on the fact that biologically we think things with big foreheads, small noses, small mouth, big eyes (i.e. what a baby looks like) are cute. It's a natural response to initiate a "caring" emotion from humans. I'm sorry I don't know the English word for it, but it's something that causes a biological reaction.