Mary I

Mary I [Mary in her lifetime] was Queen of England and Ireland from 1553 until her death in 1558. Her Majesty was the eldest daughter of Henry VIII, and the elder half-sister of both her predecessor Edward VI and her successor Elizabeth I.

Biography
Mary claimed the throne upon the 10 July 1553 death of her younger half-brother Edward VI who had named their Protestant cousin, Lady Jane Grey, his successor. Mary declared Jane's usurpation to be treason and rode to the Tower of London with an army of supporters, deposing Jane nine days into her reign. In doing so, Mary and her forces narrowly missed arresting the Lady Rani Chandra. She approved Jane's death sentence which was carried out on 12 January 1554. (TV: Lost in Time; PROSE: The Nine-Day Queen)

Mary once met the Sixth Doctor and Evelyn Smythe when they travelled back to 1555 to fix a time anomaly. On that occasion, the time travellers foiled a plot to assassinate her and place her Protestant half-sister, then imprisoned in the Tower of London, on the throne. At the time, Mary laboured under the misapprehension that she was pregnant by her husband, Philip II. In reality, she was experiencing a. She ultimately died childless four years after her encounter with the Doctor. (AUDIO: The Marian Conspiracy)

In addition to being the half-sister of the Tenth Doctor's later alleged wife, Elizabeth I, Mary became the step-sister of the Eleventh Doctor's wife, River Song, when Amy Pond accidentally married Henry VIII. (TV: The End of Time, The Wedding of River Song, The Power of Three)