I still can't keep track of my wallet or my car keys. But since the birth of my son, I find that there are many things I no longer lose. My mind has become a global positioning system.

It's in the blue bin in the closet, I say. It's under the car seat.

It's in the basement under the stairs on the second shelf.

In two seconds I can find all of my son's squished pennies and the red guitar pick he got at the Farmer Jason concert last spring. His milk-weed pod is safe in my night-table drawer, though the seeds have scattered and the fluff escapes each time I reach for a bobby pin.

I let the millipede go and can no longer lay my hands on him in the physical sense. Still, I assure my son that we know his exact whereabouts: He's coiled up tight, a circle of onyx under a lucky rock; he's happy and he's free.

Because the millipede isn't just a millipede (nor is the fish just a fish or the guitar pick just a pick). My son is giving me his trust, a sweet intangible tied and double-knotted to every stick and acorn cap. I close my hand tight around it, even when it wriggles. If I can hold on to it forever, I will.

We leave the dentist and go on to our other errands: the post office, the bank, the grocery store.

"Hold this," my son says, and I reach for a helium balloon, big and red, the type of balloon a small boy is supposed to have. I juggle it along with his hand and the bags of groceries. The air outside is cool. The wind whips at the balloon, making it dance and pull.

I hold tight to the string. My son watches with solemn eyes, making sure I don't let go.

Madelyn Rosenberg has an essay in How to Fit a Car Seat on a Camel, an anthology about kids and travel.