Oh, that was so lovely. I have tears in my eyes from the ending - so romantic and so sad, mixed. I enjoyed your OCs, and I enjoyed seeing the different relationships, and the way that reactions to gay r'ships changed through the generations. I felt very sad for Al. The parallels of the Potter/Malfoy relationships through the years was an interesting touch. (I did go to your IJ to check out the family tree, but I couldn't see it... but Adler is a descendent of Draco, yes?). Congrats on the way you used all the different new characters - the only time I felt confused was when Liam called Adler Marion, and I had a brief "there's het? Isn't Adler a boy?" moment (in the UK it would be quite unusual to call a boy that, it's a girl's name) :D Well done on a great read!
(I think it's a shame, btw, that you felt the need to warn for character death, because I know lots of people are put off by that warning. Yes, Severus and Harry are dead, but only because this fic is set mostly after their deaths, heh. I know Severus is dying in the end, but he's not dead yet! :D)