Sediments. Layer upon layer. That's how a mother's skin grows thick. A wearing down elsewhere, a re-accumulation here. Every valley exalted, every height and hill made low: the crooked made straight, and the rough places plain. He says how funny it is that we are what we eat, tells me that his voice will grow deeper because his Adam's Apple grows faster than mine. You're going to fall behind, he says. And as we walk deep into the canyon we talk about the shifting plates in his body and in the earth. He is consumed with building things, and I follow in amazement, accepting how I am worn down as the boy turns man, a fledgling mountain.