Principal had a high-profile relationship with English singer-songwriter Andy Gibb. The pair met on "The John Davidson Show" in 1981. The couple had immediate chemistry, and celebrated their love in a duet song, 'All I Have to Do Is Dream' (1981), a modest pop-chart hit that peaked at number 51 on the "Billboard" Hot 100 on September 12, 1981. The recording was the last single by Gibb, and is the only single recorded by Principal. The relationship ended in March 1982, due to Gibb's escalating drug addiction problems. As Principal explained to "People" in 1988, "Our breakup was preceded and precipitated by Andy's use of drugs," she clarified, "I did everything I could to help him, but then I told him he would have to choose between me and his problem."