Bill Mumy
Charles William Bill Mumy, Jr. , is an American actor, musician, pitchman, instrumentalist, voice actor, and a figure in the sciencefiction community. He came to prominence in the 1960s as a child actor, when he was credited as Billy Mumy. His most notable role was in the 1960s CBS scifi television series Lost in Space, where he played Will Robinson, the youngest of three children in the Robinson family.
Mumy was born in San Gabriel, California, to Charles William Mumy, Sr., a cattle rancher, and Muriel Gertrude Mumy . He began his professional career at age six, and has worked on more than four hundred television episodes, eighteen films, various commercials, and scores of voiceover projects. He has also worked as a musician, songwriter, recording artist, and writer.
Source: Wikipedia