Regulus thought. All of his jealous male feelings came to a screeching halt when he thought about Abby. In his mind, she would always be his daughter (no matter if Sirius was in the picture or not) and he would do whatever he could to protect her. If Abby was wary of getting close to Sirius then Regulus wouldn’t push her. He would stand up to Sirius and fight him the whole way if he had to.