I understand that her marriage to Crown Prince Danilo of Montenegro was a childless one -- the reason the succession passed to his brothers and their descendants (who have not strengthened genealogical ties to European royalty by marrying foreign princesses).

Otherwise, if the couple had produced heirs, one might have a different genealogical situation with the royal house of Montenegro today.

So this led me to wonder if, in fact, Crown Princess Jutta was a direct descendant of Ferdinand and Isabella of Spain ...