Patience's husband

An incarnation of the Doctor was the husband of Patience. It was this incarnation who was present at the birth of his granddaughter, Susan Foreman. (PROSE: Cold Fusion, AUDIO: Cold Fusion) One account suggests that this was not an incarnation of the Doctor before his first but an incarnation of the Other, of whom the Doctor was a reincarnation. (PROSE: Lungbarrow)

This incarnation's face was seen in the Fourth Doctor's mindbending battle with Morbius. (TV: The Brain of Morbius)

Behind the scenes
The faces of this Doctor were first introduced in TV: The Brain of Morbius but it was not until AUDIO: Cold Fusion thirty years later, in 2016 that they were confirmed to be incarnations of the Doctor.