Jet Watson is the son of Todd H. Watson and his wife Holly.
Not much is known about him, including his age. Todd deeply loves both him and Holly.
He and his mom were still on Earth when it was pulled into Final Space by a Titan in the climax of "Chapter 10". As of Season 2, they are thus either deceased or trapped in Final Space. Their fate is what drove Todd to seek revenge against Gary Goodspeed, leading to several conflicts in Season 2.