There’s only one memory of my mom in motion. It’s early on; maybe I’m three. She holds my hand out to the swing, the one Sweet Pa made after rolling a giant tire all the way back from the exchange. She lifts me into place and puts my hands on the rubber lips to hold. She spins the tire until the three ropes that hold it up are braided. I throw my head back and look up to her, pale and smiling, her face sleek and her brown hair close, like a river mammal’s. She moves her hands to my shoulders, gives a little squeeze, and lets go.