He withdrew the last of his memories, placing them into a vial, then stowing them in the box. And with the last of his magical power he placed a spell on the boxes, causing it to disappear. The last of his strength gone, he lay back upon the bed, whispering, "Sirius, I'm coming."

Learning of the future from their future kids who accidentally time travel, Harry, Ron, Hermione, and Ginny try to change the future and keep their loved ones from death.