Disclaimer: Harry Potter does not belong to me. Neither does the plot or the characters. All that belongs to me is my OCs, plot, and tea-maker. If it all did belong to me then Sirius would not be dead, but instead would be screwing Remus every chance he got. Oh, and everyone else would be screwing each other too.
AN: This story is AU. However this only because one fact has been changed. While not all that happens in this story may have happened if this fact had been changed I like to think it would.
Regulus Black's fiancée Calypso goes into a trance and makes a prediction foretelling Regulus's death by the death eaters. In the book no one hears this prediction and Regulus dies. However in my story, Regulus comes into the room for the book he forgot and hears her prediction. As a result he goes to Dumbledore, seeking asylum for him and Calypso in return for identifying death eaters. Of the names he reveals, Peter Pettigrew is included. Pettigrew is questioned under Veritaserum and sent to Azkaban. The Potters are safe, so instead the Longbottoms are targeted. The same events that transpired in the book take place, except with the Longbottoms and Neville becomes the Boy Who Lived. He is sent to live with his grandmother, who doesn't tell him of the wizarding world until he is eleven. Consequently he is raised as a muggle.
Regulus marries Calypso and produces two children. A son, Procyon Ophiuchus Black, and a daughter, Capella Eridanus Black. He never reconciles with his brother, and he is still rather evil, despite turning informant for Dumbledore. Remember he only did it to save himself and Calypso. He inherits the Black family fortune and Number 12 Grimmauld Place. This story revolves around his daughter Capella, who is not a Mary Sue. Trust me. Oh, and Sirius and Remus were and continue to be in a serious relationship.
P.S. Procyon is a star in the constellation Canis Minor, which means smaller dog. Ophiuchus is a constellation meaning serpent holder. Capella is a star in the constellation Auriga, which means charioteer. Eridanus is a constellation, meaning river. The constellations their names are found in do not have anything to do with their characters and attitudes. I just chose the names that I liked the sound of.