The Marauder's Heirs

Harry Potter, orphaned Savior of the Wizarding World who's routinely abused by his so-called family.
Neville Longbottom, almost Squib child of aurors tortured into insanity, belittled regularly by his own Gran.
Ozzy Black, unknown, or rather forgotten, Son and Heir of House Black, treated as a fugitive because of his family name upon returning to Wizarding Britain.
James Potter, Prongs, the last Lord of House Potter, killed trying to protect his family.
Frank Longbottom, Griz, tortured into insanity by Death Eaters, took brunt of Cruciatus Curse for his family.
Sirius Black, Padfoot, wrongly accused and framed by a rat bastard, was leaving a meeting with Dumbledore trying to gain custody of his godson when said rat struck.
Peter Pettigrew, Wormtail, least of the Marauders and the Death Eaters, Betrayer of the Potters, Framer of Black, murderer of 13 muggles and faker of death.
Remus Lupin, Moony, werewolf with a tragic past and a depressing present, drowns his sorrows nightly.

What happens when the 3 Godbrothers reunite for the first time in 10 years in King's Cross?

A/N: In this story Frank is in the same year as the rest of the Marauders and is a Grizzly Bear Animagus. Also, Sirius did not chase after Peter, he wanted to, but he needed to look after his own son. The Ministry wouldn't listen to his newly wedded wife, as not only was she considered a muggleborn, she was an American muggleborn, so she was viewed as a nonentity to Crouch and Minister Bagnold, Dumbledore was still completely convinced that Sirius was guilty and the Potters Secret Keeper. Though, unbeknownst to the Chief Warlock of the Wizengamot, Supreme Mugwump of the ICW and the esteemed Headmaster of Hogwarts, Sirius and his bride also thrice defied the Dark Lord, and was pregnant at the same time as Lily and Alice, but gave birth to her son 2 days before Lily and a day before Alice, making Ozzy also born as the 7th month dies. Both the Blacks and Longbottoms were targeted the next morning.