Will Robinson is a fictional male Human in the Lost in Space series. The character was portrayed on screen by Maxwell Jenkins. His allegiance / loyalty is to The Robinson Family. Will Robinson is the youngest member of the family.
When John Robinson tried to persuade his son to dive down into the water, Judy Robinson dives down instead. Unfortunately for Judy, she is unable to get back to the surface and is trapped. Will tells his father that he noticed magnesium which they could use to free Judy. Whilst exploring and trying to get the magnesium, Will falls and is separated from his father.
When Will goes off in search, he comes across the Robot which scares him. Over the course of the episode, Will befriends the Robot and takes him back to the family to assist in the rescue of Judy who is still underwater.