Hayley's 14 and protective of girls, so maybe they could become friend-ish? She's pretty innocent as an act, but is actually really devious and violent in the right (wrong?) situation, so she could definitely handle Victoria's reactions.

On the flip side, Costigan is a super reserved Bostonian, but he's secretly really protective of kids. If she latched onto him (metaphorically or literally), he wouldn't send her away and might start trying to help her out, teach her, etc? It wouldn't be a family really, but he could be a potential filler or helper or whatever!