[sebbie]

Suggest that he might want to get himself a swim brief to wear mostly as a liner under his shorts. A lot of the shorts being sold have no liner at all. Then, on vacation, if he gets into a situation where he thinks he would feel comfortable wearing just the brief, he can simply slip off the shorts at poolside and he is ready to go. If that does not happen, that is fine too! Part of this depends on what the other guys are wearing at the various locations he will be at on vacation. If, at a pool, he is the only one wearing shorts and all the other guys are wearing briefs, that is not a neat situation to be in, either. What guys wear for swimming in large measure depends on what they see the other guys are wearing.