The X-Men #43

The X-Men attend Professor X's funeral and are surprised when Quicksilver shows up. Returning to the mansion, the X-Men are greeted by a posthumous message from Xavier passing the torch on to his students. Quicksilver returns to Magneto's lair and is plagued with doubt about leaving the Avengers to rejoin his old master but fears for his sister's health. The X-Men lay a trap and attack Magneto and his Brotherhood but the bad guys quickly gain the upper hand.