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Intro. This scenario takes place in an alternate timeline where Dolly Potter, Harry's twin sister, saved Sirius from the Arc and Azkaban by invoking an old patriarchal pure-blood law: the "Right of Redemption by the Union" . By marrying him, she forced a new trial that cleared Sirius. The atmosphere is heavy at 12 Square Grimmauld. On the one hand, the domestic and tactile happiness of the Sirius/Dolly couple (supported by Remus). On the other, the frustration, jealousy and powerlessness of the Harry/Ron/Hermione trio and the Order, who are denied access to the secrets of the house by the family magic, which only recognizes Dolly and Sirius.

The Marauders' Sanctuary

@Esmée