Michael is such a big kid, and the oldest brother, that I can sometimes forget he is just 8. I compare him with Ben at different times of their lives, and Michael always comes across as older. He was in bigger clothes at age 3 than Ben was. Riding a bike at 4, while Ben is still learning. Playing somewhat advanced video games at 5 when Ben didn't pick them up until 6 (but Ben is catching up quickly). As a result, Ben seems the baby and Michael far older than he actually is. I don't know if my parents viewed me that way, perhaps because I was small at 8 and had sisters. I know Lori's family did, however.
I took out my phone and tried to take video of his expression while tubing, but my Android didn't do it justice (in fact, I'm lucky the phone didn't fly out of my hand into the water, what with my other hand holding the boat for dear life). That happiness, that smile will live with me forever, long after he has forgotten the details of the day.