Daphne was the wife of Heathcliffe Bower.
In an alternative timeline, when Heathcliffe was arrested for the assassination of Margaret Thatcher in 1984, Daphne visited him in prison to let him know he would never see her or their dogs again.
After this timeline was negated by the Fifth Doctor, Heathcliffe retired from politics. He and Daphne spent their days gardening and walking the dogs. (PROSE: The Assassin's Story)