"The trip costs money," he said.
Mom closed her eyes briefly. "Everything costs money, bud."
"I thought the school paid for it."
"I know you did."
"How much?"
"Doesn't matter."
"Mom."
She let out a breath. "Nine hundred. Total. I paid half in September. The rest is due in two weeks, and I've got it. I've almost got it. I picked up the Saturdays." She pushed the pad an inch away from her, as if it had said something rude. "That's what I meant, in January, when I said not this spring. I wasn't — I couldn't do both. And I didn't want to tell you why, because then you'd feel like you had to choose, and you'd choose wrong, because you're thirteen and the thing you can hold in your hand always looks bigger than the thing that's three months away. And I wanted you to go. I wanted you to stand in that museum. I've been wanting it since you were nine years old and made me watch that space shuttle documentary eleven times."
"Twelve," Caleb said.
"Twelve." She almost smiled.
He thought about the Air and Space Museum. He thought about the Saturdays. All those Saturdays she'd been at Lakeview Family Dental with her hands in strangers' mouths, and he'd stayed home and thought she was out at the barn with Jordan, having some secret, better Saturday without him.
"You should've told me," he said.
"I know."