Marcus Welby, M.D. (1969)

S1E16 Fun and Games and Michael Ambrose

Michael Ambrose, who lives with diabetes, decides to take drastic measures to retaliate against his father. He harbors deep resentment for John Ambrose, a successful novelist, believing that his father's actions contributed to his mother’s unhappiness before her passing. In a cruel act of defiance, Michael threatens to stop taking his insulin shots as a way to provoke John. When John leaves for a television appearance on the East Coast, Michael follows through with his threat, putting his life in jeopardy.