When the words "mum and dad" left Abby’s mouth, your eyes met Regulus’. Abby didn’t call the two of you mum and dad very much. She did when she was a little girl but as she got older it was by your names. Regulus shrugged, noticing Sirius watching from the door. The two of you didn’t have to speak to the other to know that Abby was simply stating that you were still her parents even if Sirius was back in the picture.