He originated the role of Scotty Baldwin on General Hospital in 1965, played the lead in Hallmark's 1969 The Littlest Angel,[2] and portrayed the title character in the 1973 musical version of Tom Sawyer.

After Keith was cast as the lead in the television series Family Affair, he recommended Whitaker to play the part of his on-screen nephew.

It co-starred Whitaker playing the role of an orphaned boy named Jody Davis, living in a high-rise apartment in New York City with his twin sister Buffy (Anissa Jones) and older sister Cissy (Kathy Garver), his bachelor uncle Bill Davis (Brian Keith), and Bill's gentleman's gentleman, Mr. French (Sebastian Cabot).

Jody and Buffy were originally supposed to be different ages, but the show's producers thought Whitaker and Jones looked so cute together that they changed them to be twins.

Whitaker went on to star in the 1973 Sid and Marty Krofft Saturday morning children's series Sigmund and the Sea Monsters alongside Billy Barty and Scott Kolden, and appeared in feature films, including Disney's Snowball Express (1972), The Biscuit Eater (1972), Napoleon and Samantha (1972), and The Magic Pony (1977).

[1] The following year, he appeared onstage in Judson Theatre Company's production of To Kill a Mockingbird in the cameo role of Judge Taylor.

In the premiere episode, he played the part of heckling boat owner Zach, against David Arquette's salty character Captain Barnabas.