Mikhail Kerenski

Mikhail Kerenski was the brother of Yuri Kerenski. He lived in Dagestan with his husband George in the middle of the 21st century. Due to the Doctor, and his involvement in the events on the Bowie Base One, Yuri who was destined to die was saved from being killed in the recorded explosion of the base. (DW: The Waters of Mars)

Mikhail's husband was a joker according to Yuri and bought Mikhail a car out of Mikhail's own money.