Boys Rock, Naturally

Kelton and I hiked down by the pond on The Orchard Compound today. He's three. He immediately started picking up rocks and throwing them in the water. Nobody taught him. He's never seen anyone do it. He just knows that's the way it's supposed to be. His father did the same. So did his grandfather. Why is it like this? Do little girls do this? We only had one child. He now has a one-year-old daughter in addition to Kelton. She and I will hike down by the pond next year and see what happens. If it's not a gender thing, then what compels us to want to throw rocks at water? Some primal urge? Gotta love it.