Mark Smythe

 was the son of George and Patricia Smythe and the brother of Josie Smythe. Along with the rest of his family, he was trapped in a time loop on Christmas Day because his father didn't want his mother to leave him and split up the family. When the First Doctor and his friends became trapped too, Mark was killed by his own father in his fit of rage. However, he was restored to life when the time loop reset. When Barbara Wright told George to accept the end of his marriage, Mark was freed from the time loop. (PROSE: Every Day)