3 boys and a trampoline

I usually have a "One Kid At A Time" rule for the trampoline.  We have relaxed that rule recently.  It is a great way for SJ to interact with Bob.  They have so much fun and I can't tell you how much laughter I hear when they are on there together.  Today, their neighbor boy friend came down to play.  Before I knew it, all three boys were on the trampoline.  They spent well over an hour jumping on the trampoline.  One kid would jump in the middle and try and get the other two boys to jump even higher.  I sometimes worry that someone will get hurt.  No one was doing flips tonight, so I felt it wasn't too dangerous.  I would go outside every 15 minutes to check on them.  They were having a great time.  SJ was interacting with Bob and the neighbor boy.  It is a great way for SJ to practice his conversational skills.  He was talking away to both Bob and their friend.  The trampoline also gives SJ the gross motor exercise that he craves.  The biggest benefit is how it tires out these three energetic boys.  This boy's mom told me that he fell  right to sleep shortly after he returned home the last time he was on the trampoline with the boys.  I am all for any activity that tires out Bob and SJ.