What does the last line of the story show about Mateo?

The bell over the door had rung twice since six o'clock, and both times Mateo had looked up hoping it was his aunt coming back from the bank. Instead it had been customers: a man who wanted three conchas, and a woman who could not decide between empanadas and nothing at all.

At six-forty, Mateo started wiping down the glass cases. The game at Cardenas Park started at seven-thirty, and Mario had already texted him four times: You coming or what? Tía Rosa had promised he could leave the minute she got back. He flipped the sign on the door from ABIERTO to CERRADO, even though the bakery did not officially close until seven.

He was carrying the last tray to the back when he heard a knock. An old man stood outside the glass, leaning on a cane, one hand cupped against the window to see in. Mateo recognized him. It was Mr. Navarro, who came in every Saturday morning and always paid in exact change.

Mateo pointed at the sign and shrugged in a way he hoped looked apologetic. Mr. Navarro nodded slowly, as if he had expected that answer, and turned to go. That was when Mateo noticed the thin plastic hospital bracelet still around his wrist.

Mateo unlocked the door before he had decided to.

"I'm sorry, mijo," Mr. Navarro said. "They kept me at the hospital since Tuesday. My granddaughter's birthday is tomorrow, and I promised her the pan de polvo she likes."

There were exactly two dozen cookies left in the back. Mateo boxed them carefully and tied the string the way Tía Rosa had taught him, twice around with a bow on top.

When his aunt came in at seven-fifteen, she found him sweeping a floor that was already clean. She looked at the empty cookie tray, then at the sign, then at him.

"You're late for your game," she said.

"A little," he said, and he found that he did not mind.