We never would have expected Flea (real name Michael Peter Bazalry), bassist for the Red Hot Chili Peppers, to be the voice of feral child, Donnie Thornberry. We wouldn't have expected him to be a voice actor at all if we're being honest! Flea is known for getting wild on stage, so we suppose the character of Donnie isn't totally bizarre. But we still wouldn't have picked it!
Flea voiced Donnie in The Wild Thornberrys, The Wild Thornberrys: The Origin of Donnie, The Wild Thornberrys Movie, and Rugrats Go Wild, which was a crossover with Nickelodeon's other highly popular animated show. Donnie is a jungle child that the Thornberrys end up adopting because his parents were killed by orangutan poachers. We have to hand it to him, Flea always knows how to keep an audience guessing.