Mary I
From Tardis Wiki, the free Doctor Who reference
Mary I (1516-1558) was Queen of England and Ireland from 1553 until her death. She was the eldest daughter of Henry VIII and the elder half-sister of her successor Elizabeth I.
Biography
Mary once met the Sixth Doctor and Evelyn Smythe when they travelled back to 1554 to fix a time anomaly. (BFA: The Marian Conspiracy)
She later seemingly became the Doctor's sister-in-law when, towards the end of his tenth incarnation, he married Elizabeth I. (DW: The End of Time)