In order to have a fairy tale ending...

So, while introducing Evelyn to Disney version of fairy tales, I came to realize that except for Sleep Beauty, most princesses or girls who became princesses have lost their potentially loving and caring biological mom at a very young age. Almost every story begins with the young girl losing her mother. What's up with that? I'm starting to think that the stories are telling their audiences to get rid of their moms if they want a "happily ever after" ending.