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Remus Lupin's sister should have known better. Of course her brother and his best friend, Sirius Black, would steal the one and only Harry Potter from his home with the Dursleys. When they need a place to hide the boy, where do they go? To Fiona Lupin's home.

Sirius and Remus own a small bookstore near Privet Drive. Harry loves it there despite not really being allowed in. When Sirius and Remus discover how he is treated by the Dursleys what can they do but take him away?

This is an alternate universe where Lupin has a sister, Sirius doesn't go to prison, and he and Remus save Harry from the abusive Dursleys to raise him themselves. I didn't come up with this idea myself. I got some of it from another fanfiction called Stealing Harry. It's on Ao3 and I highly recommend it.