I agree I would hate if marvel made it so Magneto killed Natalya for no reason, I hope it doesnīt happen, still I believe the reason why they didnīt take the steps to actually tell the entire story about the twins is because they planned to undo it from the beggining hence we have Vision keeping his mounth closed and Agatha and even Natalya just chaging the subject when they could have easily said to Wando who her father was but with the way marvel leave the story they donīt even need to retell the story about Natalya, just say their father was magneto, he lived a big part of his life on Europe looking for Magda so itīs not far fetched to see him and Natalya meeting and having a relationship. Wanda can keep her mystic roots with her mother while Pietro gets the relationship with Magneto back.