(11 May 1959 - 7 February 1968) (his death) 2 children
1. Allyson Lee Adams (23 February 1960)
2. Jeb Stuart Adams (10 April 1961)
Adams married former child actress Carol Nugent in 1959. Nugent had appeared in an episode of The Rebel. They had two children, Allyson Lee Adams (1960) and Jeb Stuart Adams (1961) who both later pursued careers in the film industry.
Sometimes acrimonious marital problems reportedly interfered with his ability to get lucrative acting parts after 1963. While promoting Young Dillinger during a television appearance on The Les Crane Show in early 1965, Adams "shocked" the viewing audience with an announcement he was leaving his wife—seemingly without telling her first. The couple publicly announced a reconciliation a week later but his career and personal life following this episode have been characterized as a "tragic freefall".
Adams and actress Kumi Mizuno may have had a short affair while he was working in Japan. "That's one of the reasons my parents were divorced", his daughter, playwright Allyson Lee Adams, later said. "My dad had a penchant for becoming infatuated with his leading ladies. It was a way for him to take on the role he was playing at the time."
By July 1965 they were legally separated and Carol filed for divorce in September. The following month, while Adams was in Japan, Carol was granted a divorce and custody of the children. In January 1966 Nick and Carol announced another reconciliation on a local television show, Bill John's Hollywood Star Notebook. However in November 1966 Carol resumed the divorce proceedings and obtained a restraining order against him, alleging Adams was "prone to fits of temper" and in an affidavit charged he had "choked her, struck her and threatened to kill her during the past few weeks." On January 20, 1967 Adams was waiting for a court hearing to start when he was served with a $110,000 defamation suit by Carol's boyfriend, Paul Rapp, who later married Carol. Nevertheless, nine days later he was granted temporary custody of the children. His son Jeb Adams later recalled, "He saw it as a competition, basically, more than anything of getting custody of us. But, a matter of a week or two later, he gave us back to my mom" and Carol later regained legal custody of the children.