Ugh... I don't like that they put the son in who won't be born if the timeline goes all differently. Adds some extra dimensions of tragedy here that make me unhappy.
What kind of stupid plot is this? villain pretends to be be dead, why? Duke adopts a daughter to replace his actually alive daughter, why? if they wanted to get the prince to marry the villain why pretend to be dead at all? They're a ducal house the chance of a prince marrying someone from their family is very high anyway, no need to freaking adopt a nobody mc.