I Do not know about the reason for her buzzcut. But when i had to get one it was because at a young age shaving head is easier and allows for better hairgrowth . it also is simple style to keep and it is tradtion to for some
In some cultures they believe that this will make it grow thicker. It doesn't actually work although shorter hair and removing baby hair that would have eventually been gone anyway makes it look thicker. But since it's common enough in those cultures, it doesn't do any harm even if it doesn't help.
It amazes me these kids are brought in and have their heads shaved, no crying, no fits, they sit there obediently get their haircut .. that's how it should be kudos to those parents and kids!
Because they are not from the West. Kids in these cultures still know how to behave and aren't indoctrinated into having to have long "stylish" hair to be considered valuable.