* Mary, Queen of Scots, was never married to anyone named "Bloody Mary." "Bloody Mary" is a nickname given to Queen Mary I of England, who was the daughter of Henry VIII and Catherine of Aragon.
* Mary, Queen of Scots, was married three times. Her first husband was Francis, Dauphin of France, her second was Henry, Lord Darnley, and her third was James Hepburn, Earl of Bothwell.
* Mary, Queen of Scots, had one child. She had a son, James VI of Scotland (who later became James I of England).
So, Mary, Queen of Scots, had a son named James through her second marriage to Henry, Lord Darnley. The nickname "Bloody Mary" refers to a different Queen Mary, and it is not related to Mary, Queen of Scots, or her child.