We do not know who the parents of Marin Boucher. It is only speculation that he was the brother of Gaspard Boucher, Ans speculation is not proof. ust because they were from the same village in France DOES NOT mean they were brothers.
The PRDH says that the parents of Marin are unknown, Unless someone can produced documentation (i.e. baptismal or marriage record) listing who is parents were, we do not know who they were. And we can not assume that Gaspard & Marin were brothers.