Ultimate shoulder rides

walking on a trail the one day, I saw a sight I don't often see.  A little ways off this girl who looked to be about 17 or 18 was giving a shoulder ride to a boy who appeared to be around the same age. I don't know how long she had been carrying him. I did not see when he got on her shoulders, the ride was already in process when they came into my view, but I did see her carry him for several yards.

Bonus membership plz.