“Has to be. The ticket numbers matched up,” Tess said. She combed through the list of names, but the dress could have belonged to any of them and none of them. “Okay, so the only embellishment on the gown was that lace with the little hearts.”

“Uh-huh,” said Theo, who didn’t care about lace or hearts.

“Maybe it means something.”

“What does?”

“The hearts.”

“As in, we should have counted the hearts? Maybe the number of symbols is important.”

When Jaime finally arrived, he used his phone to send the photos of the dress to the twins’ computer. They blew up the images on the screen. They counted the number of hearts on the lace and got one hundred and eleven.

“Doesn’t mean anything to me,” said Theo.

“Me, neither,” Jaime said.

Theo continued to root around in his shaggy hair, scratched. “I don’t think the lace is important. It’s just lace. Lace is lace.”

“Like I said the other day, there’s got to be something else hidden in that gown. In the hem or the undercoat or whatever you call what goes under these old-fashioned dresses,” Jaime said.

But something was itching at Tess’s nightmare-exhausted brain. She’d been so scared during the night, and even in the morning. But then she saw the sun on her mother’s face. And felt . . . love.

Maybe the gown wasn’t important, the number of symbols wasn’t important, but the symbol itself was.

Hearts. Love. Hearts. Love.

“Love!” she said. “Love is the thing!”

“Okay,” said Jaime, looking at Tess as if she’d grown another nose.

“No, you don’t understand. The heart means love.”

“We’re aware of the symbolism, Tess,” said Theo. “We all got the same Valentine’s cards in the first grade.”

“The only Valentine’s Day cards you got were from Mom and me,” Tess retorted. “I’m saying that what’s important is the symbol of love on the lace. Love on the lace, love on the lace.” Her eyes went wide. “Lovelace! Ada Lovelace!”

Jaime frowned. “Ada Lovelace? I don’t remember that name on our list.”

“She’s the daughter of Lord Byron, the poet. She was a mathematician. Studied computers in the 1840s.”

“I thought that the Morningstarrs were the only ones working on computers and robots and that kind of thing,” Jaime said.

“No, said Theo. “A guy named Charles Babbage was working on them, too. Ada Lovelace worked with him.”

“And she was ignored for a long time. A lot of people said she was delusional,” said Tess.

“Huh,” said Theo.

Tess’s excitement illuminated the foggy corners of her mind, brightening everything. “What do you want to bet she corresponded with the Morningstarrs? She must have. They were building machines unlike anyone else. Maybe she even came to New York City.”

“I’ve never read anything about that,” said Theo.