Tegan Jovanka's father
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William Jovanka was the father of Tegan Jovanka. He had died by 1981. (PROSE: Divided Loyalties) He owned a farm in Australia. (TV: Logopolis)
He always used to say that "if" was the most powerful word in the English language. (TV: Castrovalva; AUDIO: Psychodrome)
William was married to Joy, Tegan's mother. (PROSE: Divided Loyalties) When Kamelion tapped into Tegan's memories, he was overwhelmed by childhood memories of Tegan's parents and Aunt Vanessa, as well as the Fifth Doctor's memories of Gallifrey. (PROSE: Qualia)