Families are an essential part of the history of the X-Men. Because they gain their powers through natural genetic evolution, their families tend to be filled with mutants. The fact that X-Men books are all the equivalent of long-running soap operas allows for these families to grow increasingly complex with every passing year. Decades of relationships, flings, and tampering by Mister Sinister have given room for some incredibly complicated family trees.
Source：https://www.cbr.com/5-most-complicated-x-men-families/
