Comments of chapter undefined of Devil's Eyes

This is what I'm trying to work out!! If they are cousins, can werewolves mate with their cousins and it's not considered weird? (assuming I'm reading it correctly... mafia = werewolf rival packs, intense feelings = mating bond) Or are they just close family friends who call each others parents Aunty/Uncle? In which case, just get together already!!!! Also... when is Bella gonna turn 18 and realise she is mates with Xavier!? Need to keep reading... lol