Ava’s phone call

Just heard that she calls Charlie. He's been working for her. So Xander and Phillip think they got something over on each other and really Ava is running the show, through Charlie.

also, we know Charlie is going to be the person who raped Allie. My question is, is he Tripp's twin? Or is he a half sibling? If their twins, then that would make Charlie Steve's son too.