What happens to the character "Noah" after a certain point in film?

Rating: Null/10 (23 May 1999)

After watching this movie many times on TV, we've been puzzled by the character named "Noah", played by Frank Sully. He is last seen with the men in the river after finally getting to California (he's playing with a toy boat). But that's the last time he's seen in the movie, with no explanation as to his disappearance from the movie from this point, and no reference made to him from this point onward. What happens to this character, and how and why does he just "disappear" without explanation?