User blog comment:Gundam Legilis/Volume 3 Opening Review/@comment-4367432-20151016005103/@comment-24053809-20151016064654

My guess is that there's been this ongoing fued between the Branwen side of the Rose family and the Schnees for quite some time now. This might be a stretch, but I think that it might mive something to do with Summer. Maybe Qrow and his team were hired by the Schnees for a mission that caused the death of Summer and now Qrow holds her family responible for it.

As I said, this is a big stretch because Yang and Ruby are on good terms with Wiess and had no form of hostility when they first met. Qrow, along with Tai Yand and Raven perhaps, have been keeping this a secret from the girls all this time in order to hide the truth from them.

Again, this is just my thought on it so if anyone has a better theory, I'd like to hear your thoughts.