William Jayne (born April 10, 1969), known professionally as Billy Jayne and previously Billy Jacoby, is an American actor, known for his roles in the teen comedy film Just One of the Guys (1985) and in the teen sitcom Parker Lewis Can't Lose (1990–1993).

[3] The director needed someone to play Jacoby in flashbacks, and Jayne was selected and began his career.

Jayne was a child actor from the mid to late 1980s, starring in numerous guest appearances on TV shows such as Trapper John, M.D., The Golden Girls as Blanche's 15-year-old rebellious grandson David, The A-Team, and 21 Jump Street.

From 1990 to 1993, Jayne starred in the teen sitcom Parker Lewis Can't Lose alongside actor Corin Nemec.

After the series ended, he had smaller roles in shows such as Renegade, Murder One (1995), Walker, Texas Ranger (1996), Charmed (1999) and Cold Case (2009).