Conversation so far:
Was Isabella I of Castile married?
Isabella I of Castile marriage to Ferdinand II in 1469 became the basis for the de facto unification of Spain.
Where was Queen Isabella's empire located?
Isabella I of Castile controlled Spain, a huge overseas territory in the New World, the Asian archipelago of the Philippines, and territories in Europe, Africa and Oceania.

Question: Do they have any kids?
Self-contained rewrite: Did Queen Isabella and King Ferdinand II have any kids?