In 1957, she and child actress Evelyn Rudie played the daughters of John Wayne and Maureen O'Hara in The Wings of Eagles.

In 1958, Gibson portrayed Cary Grant's daughter — with Paul Petersen and Charles Herbert playing her brothers — in the romantic comedy Houseboat, which also starred Sophia Loren.

Gibson played a schoolgirl at a small private school run by two friends (portrayed by Audrey Hepburn and Shirley MacLaine) who were falsely accused of being in a lesbian relationship which was somewhat risque for its time.

That same year, in One Hundred and One Dalmatians, Gibson voiced the puppy named Lucky, alongside Mickey Maga, Barbara Baird, Sandra Abbot, and several other children.

By age 19, Gibson, along with other acting friends, found it difficult to get roles due to overexposure, and the casting directors were looking for "new faces".

Petersen remained a lifelong friend and in 1990 founded A Minor Consideration, a nonprofit group devoted to protecting and advancing the interests of child actors.