There’s Nothing In This World I Wouldn’t Do (смешанная)

Harry leaned over to fiddle with the gold ring on Sirius’ finger, biting his lips. “The Dursley’s told me it was wrong for two men and two woman to be together.”
 
Sirius tensed. “And what do you think?”
 
Harry shrugged. “You’re better parents than them, so I don’t believe a word they’ve told me.”
 
Sirius barked out a laugh and pulled him closer, kissing his hair. “Oh, we’re so proud of you, Prongslet.”
 
 
Or, where Harry is taken from the Dursley's when he's a child and is instead raised by Remus and Sirius.