Prince Charles will never be King
He’s the least favourite royal, and rumours abound that he’ll never be King, but don’t count the Prince of Wales out of donning the crown when his mother, Queen Elizabeth II, passes on. According to Royal Household’s official website, successions are governed by Parliamentary acts (the latest from just 2013!), and one must be: Protestant; descended from Princess Sophia (Electress of Hanover and granddaughter of James I); in communion with the Church of England (and swear to preserve it and that of Scotland); eldest in line. Prince Charles meets all these requirements, and the royal website goes so far as to identify the next in line!
Prince Charles will be denied the crown anyway
The rumours may be persistent, but Parliament won’t deny the throne to a “next-in-line” unless the heir is found guilty of “misgovernance.” There are no allegations against Prince Charles. He’s also a stickler for maintaining the best possible public image.
Duchess Camilla is Catholic
Camilla has been Prince Charles’s wife since 2005. Prior to that, she had been married to Andrew Parker Bowles, who was Catholic, and their children were raised as Catholics. She, however, is not Catholic, and her marriage to the Prince was made official in the Anglican church. But none of this even matters because the Succession to the Crown Act of 2013 overturned any previous law by which a next-in-line would be disqualified for having married a Roman Catholic. So, Prince Charles’s claim to the throne would stand regardless of Camilla’s religious affiliation.