Diagnosed with multiple sclerosis in 1977.
After going public with her MS, she was asked to participate in a National Multiple Sclerosis Society ad campaign. She initially turned it down, telling the Los Angeles Times that she had thought that the organization wanted her to do what she called "poor me" ads. She changed her mind after learning that the campaign would feature people with MS doing everything from scuba diving to skydiving. The 1988 ad showing Rhue in her wheelchair noted that she "can't walk so well anymore, but she can still perform." It was headlined, "Even with MS, Madlyn Rhue Is On a Roll."
After landing the role in Houston Knights (1987), she placed a full-page ad in Variety headlined, "See the new Madlyn Rhue".
The last television series Rhue appeared on was Murder, She Wrote (1984), in which she played the recurring character of a librarian. Series star Angela Lansbury reportedly had heard that Rhue was in danger of losing her Screen Actors Guild medical coverage because she was short of meeting the annual earnings requirement. Landsbury created the librarian character for Rhue and brought her in every three or four episodes so she could meet the requirements.
Ex-daughter-in-law of Carleton G. Young.
Passed away one year after her ex-husband Tony Young. Young died of lung cancer in 2002.
Both Rhue and her former husband, Tony Young, were guest stars on the original Star Trek (1966) series. He was with France Nuyen in Star Trek: Elaan of Troyius (1968) and she was Ricardo Montalban's character's (Khan Noonien Singh), love interest in Star Trek: Space Seed (1967).
Besides playing Ricardo Montalban's love interest in Star Trek: Space Seed (1967), she also played his wife in Bonanza: Day of Reckoning (1960).
Close friends with Suzanne Pleshette and Faye Michael Nuell.
Was a conservative Republican who supported the presidencies of Richard Nixon, Gerald Ford, Ronald Reagan, George Bush, and George W. Bush.
During her appearance on "The Tonight Show with Johnny Carson" (October 18, 1974) she said she is half Jewish, half Catholic.