Continuity mistake: In the scene where Lyle and Ursula slide through the river then over the falls, when they go over the waterfall they are both dry.
Continuity mistake: In the scene where George hits the tree and falls on a branch with green stuff on it, you can catch a glimpse of his briefs.
Continuity mistake: In the scene where George is teaching Ursula how to swing on vines, George crashes into a tree. When he lands on the net the gorillas have you can see bits of a black trampoline underneath the cover.
Continuity mistake: Toward the end of the movie, in the scene where Lyle and Ursula are in the rapids, Ursula takes control of the paddles. In one shot she has both paddles in her hands. In the next shot you can see one floating down the rapids, and when the shot switches again, you see that she has both paddles in her hands again.
Visible crew/equipment: The last time we see George in California he is running down the road. When the camera moves up you can see the shadow of the camera man and camera crane on the ground as clear as day.
Audio problem: During the lion fight scene, George says "Here kitty, kitty, kitty" but his mouth does not move at all.
Audio problem: When George is in Ursula's apartment after his shower, Ursula covers his behind with a bowl, saying "Cover the booty." Her mouth doesn't move.
Visible crew/equipment: When George is running back to the jungle from the city, he journeys in a boat along a river. Unfortunately, you can see the wake made by the camera boat in front of the boat in which George is travelling.
Continuity mistake: In the shot where George is going to save the gorilla, the shoes he uses swap between shots.
Continuity mistake: When Lyle is covering himself with berry juice to represent blood, he swipes some across his forehead. His forehead already has the red mark on it before his hand crosses his forehead.
Deliberate mistake: Every time George swings into a tree, there is a George shaped impression created. However, in the next scene the tree is back to its natural shape.
Continuity mistake: When George pounds his elbow into the lion, the lion's head is facing the same way George is going as he jumps up, but as he lands and the lion howls in pain, the lion is facing the other way.
Answer: They never mention what ultimately happens to his parents. However it's mentioned they "searched high and low" for George and never found him. The animation even shows all the passengers calling out for George, to suggest they also aided in the search.