Well, the real story went that Ed Gein and his older brother grew up with their mother. The 2 worked odd jobs around town to support them and their mother from very early ages. Ed Gein was unhealthy in the way that he loved his mother, and she raised the boys under the impression that girls are evil whores, all of them. A fire broke out once in the woods behind their home, and the fire department arrived to find that Ed's older brother had been caught in it and died. They also found trauma indications on his head, which suggested that Ed, as a very young child, murdered his own brother. The assumption is that his brother wasn't quite as submissive to the shit that their mother would tell them and that Ed didn't want to be bad for not agreeing with her.
Then, he started digging people up.
The whole notiont of the "family" was fake to begin with, but it was excellent for the purpose of the movie. That's why I'm so curious to see how they rewrite the origin. If done well, this movie could really be creepy as hell, so I've got my fingers crossed.