Chapter 4 Sirius sat in his room, going through his his old school trunk, which was full of pictures and memories of times long past, among these things he found an envelope addressed to him.
He listened carefully , making sure no one was coming before sitting on his bed and opening the envelope.

Inside he found a letter:

Sirius, if you are reading this then it is too late for me to warn you which is why I have enclosed something that could help you and the Potter child. To use this you must go back to Godric's Hollow. I know we didn't always get along but you must believe in me. In doing so you will find a new meaning to the promise you so often shared with your friends You must be willing to face an incredible evil and put your self in the path of destruction. Be brave my dear brother, as brave as I've always known you to be. Best of luck to you and tour friends

Regulus

Sirius's mind reeled what could his brother possibly have saved for him, and why would he have to go back there. Slowly, he reached into the envelope and pulled out an hourglass looking device that he recognized as the time turner their father had given Regulus for his birthday when he had turned eleven.