So let's say through a series of family tragedies Catherine of Aragon becomes Queen of Castile upon her Mother, Queen Isabella's death. So let's say for this scenario, Isabella, Miguel and John die as otl, Joanna's ship sinks on her way to Burgundy and Maria of Aragon dies of an illness. What would a Queen Catherine of Aragon look like? Might Catherine marry Duke Ferdinand of Calabria to keep the Trastamaras alive? How would Ferdinand of Aragon react?