Most people have them once a year. Some have multiple birthdays due to various reasons. Some lose their birthday (because they changed their identity, lost their memory, other reasons), so have to make up another one. Why?
Because, birthdays are one of the special days when you can reasonably expect the people around you to treat you like you’re royalty. Sort of. For kids, this means large celebrations with balloons and games and classmates they might never see again after the year; celebrations for teens and young adults range from elaborate celebrations to a fun day out with a few close friends; older people tend to have smaller celebrations, usually within the family, but there’re always exceptions to that.
In other words, special treatment on birthdays, usually.
But if you really think about it, x number of years ago, we didn’t do much but survive, which we’re supposed to do anyway. Mothers did most of the hard work during our birth. So when we’re celebrating birthdays, we should also be celebrating mothers because without them we wouldn’t be here. We wouldn’t be here without our father either, but our father didn’t go through hours of labour to get us.
So maybe, during your next birthday, give your parents a hug or something, since without them, you wouldn’t be celebrating anything.