Sybil Stockdale is the wife of the late Vice-Admiral James Bond Stockdale, who survived 2,621 days in the infamous Vietnamese prison known as the "Hanoi Hilton." In a letter he wrote her from captivity, he made an unusual literary reference that aroused her suspicion.
Correctly guessing that her husband was trying to relay a secret message, she passed the letter on to the Office of Naval Intelligence. Over the next few years, Sybil agreed to allow concealed information to be passed on to her husband through their correspondence, despite the danger this posed on his life. At one point, Sybil even received formal training by the CIA in covert communications.
In 1973, Stockdale was finally released and returned to the U.S., where he was reunited with Sybil. They would go on to pen a co-memoir together, "In Love and War: The Story of a Family's Ordeal During the Vietnam Years," which became a national best seller and a successful made-for-television movie.
While Sybil initially agreed with the U.S. government's request not to publicize POW torture at the hands of the North Vietnamese, she eventually became frustrated with its secrecy. As a result, she co-founded the National League of POW/MIA Families -- a nonprofit organization that worked on behalf of American Vietnam-era missing in action and POW families.