Premise: Charles II of England . In 1679 , Titus Oates 's revelations of a supposed `` Popish Plot '' sparked the Exclusion Crisis when it was revealed that Charles 's brother and heir ( James , Duke of York ) was a Catholic . Charles 's wife , Catherine of Braganza , bore no live children , but Charles acknowledged at least twelve illegitimate children by various mistresses . He was succeeded by his brother James .
Hypothesis: Charles II of England had a male sibling.
Label: ENTAILMENT