Mandy finds the jar of baby teeth in her mother’s sock drawer, the week after she turns eleven.

Daydreams about a frothy fairy with butter-blonde curls leaving coins under her pillow have long since evaporated; this is the first of many horse girl summers. The jar, white china with hand-painted blue flowers, is nestled between the tight-rolled pairs of black dress socks that Mandy was sent to borrow; at ten, she already wears the same size as her mother. Mandy takes it out without hesitation, knowing that it is for her, it is hers. The lid clicks against the jar’s hidden lip and Mandy opens it, holding it up to the light from the window.

It’s not a full set. She remembers losing a tooth while playing tag with the neighbor kids in their yard, and another that disappeared into the coat cranny of her second-grade classroom when, after recess, she bit down on her cold wet mitten to pull it off her hand.

All eight molars are there, though, pearly and opalescent and not quite real-looking, like dried bubbles of Elmer’s glue. She presses her thumbnail against one, half-expecting it to leave a mark. The edges where the root died away are sharp and thread-thin, protecting the stained crescent at the center even though there is nothing left to guard. When Mandy pinches it, the points bite into her fingertip. It seems to her as if that should have been the edge turned out against the world: ragged, ready to tear.

“Mandy?” her mother shouts, from downstairs. Her shoes clack up the staircase, but the carpet in the upstairs hall suffers the high heels in silence. She stops in the open doorway, looking at the jar in Mandy’s hand. “What are you doing? Your father and I are ready to go.”

Mandy slides the lid back on. The ceramic squeals unpleasantly, a betrayal of the delicate design. “These are mine.”

“What would you even do with them?” A question to answer the question that Mandy didn’t ask. She strips the jar from Mandy’s hand and settles it back into the drawer. “Come on now. We should have left for church five minutes ago.” Still, she finds the time for a skeptical up-and-down look at Mandy’s black slacks and blouse. “Are you sure you won’t wear that dress? It’s so pretty on you.”

Mandy squirms. “Do I have to wear pantyhose with it?” The slacks are uncomfortable enough as it is, tight in the thighs, not stretching like her jeans do. Hose are worse, with the control top biting into her belly and leaving red marks for hours after she’s free. They always leave her feet sour and sweaty, too, and she’s afraid the other girls in Sunday School will notice.

“Of course you need pantyhose.”

“Then I’ll wear pants.”

Her mother’s eyes narrow. “You look like a linebacker in that blouse.”

Even knowing this might have been coming, Mandy freezes. A deer in headlights doesn’t expect to be saved by its stillness; this is a hopeless gesture, not a sly one.

“Sit down,” her mother says briskly, and sets down her purse. “Unbutton your blouse and let’s see what we can do.”

Goose-bumps prickle Mandy’s arms as she perches on the edge of her parents’ bed. Her training bra pinches her under her armpits; she picks at the ugly little flower on the front of the band, where the two V’s of fabric meet and join.

“Hold still,” says her mother. “This will only hurt for a second. Like popping a pimple.”

Popping pimples hurts, too, of course, and sometimes, when her mother’s fingernails dig too deep, it leaves a scab that softens into a scar. Mandy watches her mother slide open a drawer in a different dresser and take out the scalpel case, holding the blade up to the light, taking one efficient swipe with an ethanol wipe. When she sets it to Mandy’s shoulder, parting the skin, Mandy doesn’t flinch. She feels the scalpel slide between muscle fibers of her deltoid; a solid section separates from the rest. There’s an acute tugging sensation before her mother tidily severs the inser...