Drama version: If a Gryffindor Sirius is born in the pure Black family, the consequence will be a complete break between Sirius and the Black family; if before the duel between the savior and the Dark Lord, a Slytherin Angelica is born in the Potter family, what will be the consequences?
The true version: The time-traveling heroine uses a cheat to join forces with her future father-in-law to weaken the Dark Lord, allowing her savior brother to give the Dark Lord a final blow, and is seduced by her future husband at school.
Note: I don't really like the dark conspiracy genre, so I keep everything simple (simple simplicity) - and when I want to write about palace conspiracy theories, I will definitely let you know in advance...