In the beginning, Maud didn't want to have a little sibling. Imagine her shock when she got three of them, all of a sudden. It was weird, having a trio of younger sisters around. She was responsible of them, and she had to make sure that they were ok.
That's probably why she's so "boring", according to everypony else. But that's ok.
Who wants to punch me in the face for the title pun?