Dr. McCoy may not be the central focus of as many episodes as Kirk and Spock, but Star Trek wouldn't have worked nearly as well without him. At some point before joining the crew of the Enterprise, McCoy was married, but the marriage ended in a bitter divorce. The identity of McCoy's ex-wife remains unknown, but his daughter is mentioned in Star Trek: The Animated Series season 1, episode 6, "The Survivor." However, the character of Joanna McCoy was conceived years before, sometime between the first and second seasons of TOS.
Dr. Bones McCoy's Daughter Joanna In Star Trek, Explained
McCoy's Daughter Was Only Mentioned In One Episode Of Star Trek: The Animated Series
Although Joanna McCoy never appeared in TOS, she was added to the series bible between the show's first two seasons as the result of a conversation between writer D.C. Fontana and DeForest Kelley. In the Star Trek: The Animated Series episode, "The Survivor," Dr. McCoy mentions that his daughter was in school on the planet Cerberus in the year 2259 when a crop failure occurred. Trader and philanthropist Carter Winston used his personal fortune to deliver food and goods to the planet, and Dr. McCoy got the chance to thank him in 2269.
According to The Making of Star Trek, Gene Roddenberry once had plans to introduce Joanna McCoy in Star Trek: The Original Series season 3. Joanna would have become a love interest for Captain Kirk, leading to a conflict between Kirk and McCoy. An early draft of TOS season 3, episode 20, "The Way to Eden," included this storyline, but Joanna later became Irina Galliulin (Mary-Linda Rapelye), a former girlfriend of Ensign Pavel Chekov (Walter Koenig). Joanna appears in numerous works of Star Trek tie-in fiction, often working as a nurse or another medical professional.
Bones' Father Is More Famous, Thanks To Star Trek V
McCoy's Most Painful Memory Involves The Death Of His Father
Not much about Dr. McCoy's family was ever revealed by TOS, but Star Trek V: The Final Frontier explores the tragic story of the death of his father. When the Enterprise encounters Sybok (Laurence Luckinbill) in The Final Frontier, the renegade Vulcan uses a mind meld to reveal the most painful memories of the ship's crew. He then takes away this pain, earning him the crew's loyalty. Kirk refuses to share or shed his pain, but Dr. McCoy's most painful memory involves his father, David McCoy (Bill Quinn).
In his old age, David McCoy began suffering from an incurable and incredibly painful disease, and he eventually convinced his son to help him end his life. Tragically, a cure for David's illness was discovered soon after, meaning Bones could have saved him. Dr. McCoy carried this guilt with him for much of his adult life and is forced to relive these events thanks to Sybok. Despite being one of Star Trek: The Original Series' main characters, much about Dr. McCoy's official history remains unknown, and his father and daughter are only briefly referenced.
