What a moving story, Becky! You have truly captured the spirit of the two sentences in "Harry Potter and the Prisoner of Azkaban" that left the deepest impact on me: " 'Then you should have died!' roared Black. 'Died rather than betray your friends, as we would have done for you!' " We see in Sirius the qualities of a true friend, and I'm sure many of us are moved to ask ourselves if we would have been so loyal in his place.
Here's wishing you all the best with your future stories!