Was the actor Mel Gibson in TV series called The Sullivans?

No, Mel Gibson was not in the Australian TV series "The Sullivans".

"The Sullivans" starred * Norman Yemm (as Dad), Lorraine Bayly (as Mum), Paul Cronin (as Dave), Gerard Maguire (as Toby), Caroline Gilmer (as Rosie), and Rod Zuanic (as Jimmy).

Mel Gibson's early acting career primarily involved Australian films and TV shows. He did not appear in "The Sullivans".