Yeah, much too close quarters for bubbles! He'll probably be absolutely fine with everything going on around him. Worse comes to worse, start playing games--I Spy, name your favorite Disney villain, favorite movie, favorite ride, favorite...you get the idea. Quiz one another. Play Disney trivia.
My kids were early spellers and I can't tell you how many times we played the alphabet game--on car rides, while waiting in lines, passing time in doctor's offices, whatever it was. So it would be let's do foods of the alphabet. A is for apple. B is for banana, etc. Everybody playing takes a turn with the next letter. We'd do foods, animals, places, cartoon characters, movies/TV. This is the one I always pulled out when I wasn't prepared and we needed a distraction!