It's good to relieve oneself when the opportunity presents itself.
Brandon's mom suggests Brandon use the restroom before they leave the drive would be along mostly deserted highways.
Brandon wants to play another video game before the trip.
Brandon decides to use the bathroom and then plays a video game until his mom calls him to leave.
Brandon gets involved with the video game and forgets to use the restroom.
Brandon has a comfortable trip and enjoys the time with his mom.
Brandon has to pee by the side of the road and listen to his mom rant.