So, I think I decided on some background information.
Lets see how long it lasts until I change it! : D
So, instead of Tabbi and Tadhg living in NYC before the attacks and moving, I think that only their grandmother lives there. Tabbi has always lived in the same house in Wes Chester county and, well, as for Tadhg, I'm not sure. A while ago I had the idea that he grew up in Boston but his family moved back to the New York area after a fire, moving into their apartment in Titusville right before the attacks. It would account for why Tabbi is so excited to show him around the city if he had just recently moved there and hadn't visited the area very often... but then I still like the idea of him just growing up in the New York area with Tabbi as well.
Crow lived on Long Island and was on a subway with his dad when the bombs went off. By pure luck (and possibly an early manifestation of his power's secondary ability to manipulate metal) he was one of the only, and by far the youngest, person on the entire train to survive. He was in a coma for 2 days, but otherwise relativly unscaved, and became a national human interst story. National news recoginition, talk shows, all that great stuff. Part of the reason he uses the name Crow is because everyone knows about David-Anthoney Politucci... sometimes he still gets recognised. He hates it and it only fuels his survivor's remorse.