I can tell we’ve reached the time to hit it out of the ballpark when I hear Aunt Patty squeal, “ ‘Ballerina’! I love this song!”

I panic when I see Grandpa Joe hold out his hand to Aunt Patty.

“May I have this dance?” he asks her.

I don’t know what Grace has planned, but I don’t think I have time to sit around and find out. I wiggle my way over to the dancing duo. But just as I’m close, Luis gets to Grandpa Joe before me.

“Hey, Joe. Hey, Patty,” he says. “I think you’re dancing a little close to the edge of the pool. So why don’t you guys mambo your way over?” he asks, doing a funny little dance move, and starts to drag Patty away from the pool and lead her over to a grassy area by her elbow.

I’m so shocked I can’t believe it. Of course! Just tell them, hey, you’re dancing a little too close to the pool’s edge. I shake my head and smile in relief. We did all that agonizing about getting Patty and Joe away from the pool for nothing.

But I’m celebrating too soon. Patty refuses to move. “I can’t dance on the grass,” she says. “Look, I have heels on. They’ll sink in the grass and mud. I need to stay here on the concrete.” She looks up at Grandpa Joe and smiles. “And I feel safe with Joe! If I start to slip, you’ll catch me, won’t you?”

Joe puts his arm around Patty’s waist and smiles. “Of course!” he says. “I wouldn’t let anything happen to you!”

Luis turns to me and shrugs as if to say, I tried. So it’s up to me. I walk over to Joe and tap him on the shoulder.

“Hey, Joe, sorry to bother you,” I babble as I hold his arm and pull him away from Patty so he can’t move away from me. “Can I talk to you for a minute? It’s important.”

Grandpa Joe turns toward me and grins politely, but I can see that he’s not feeling as polite as his smile seems.

“Any other time, kid, but not right now, okay?” he says. “I think it’s apparent that I’m a little tied up at the moment. You see, there’s a beautiful girl here who wants to dance. And I want to dance with her. So you’re going to have to wait.”

I can’t let it go. Just one small chance—that’s all I have.

“Um, Joe? This . . . this . . . it just really c-c-can’t wait . . . ,” I stammer.

Grandpa looks concerned for a minute, and that’s when I make my big mistake. I relax. When I do that, he can sense that it’s probably not the emergency I’m making it out to be. And then, out of the corner of his eye, he sees my “cousin” John start to move in on Patty.

“Look, kid, I’ll be right with you, okay?” he says, sounding totally annoyed now. “Just after this dance!”

Grandpa Joe moves back away from me and puts an arm around Aunt Patty’s waist.

“Sorry, she promised this one to me,” he tells John. “C’mon, Patty.”

No! No! No! No! No! I scream inside my head as they start to dance. Luis and I watch helplessly. Joe is staring at Patty with a huge grin on his face as they dance, totally oblivious to the fact that his foot is right on the pool’s edge. It’s going to happen any second now, I think miserably. This entire trip back in time has been a total waste.

“JOOOOOOE!” Grace screams as she stumbles across the backyard waving her arms frantically toward Grandpa and Aunt Patty. “Don’t dance with her! Dance with me! I . . . I . . . I LOVE YOU!”

Luis and I are frozen in place. We’re totally in shock. The rest of the crowd starts to buzz with chatter. They’re shocked too, but they’re also pointing and laughing. I guess it’s because Grace is the girl who just bumbled her way across the mambo floor.

I try to wrap my head around it.

Shy Grace. Quiet Grace. Stay-behind-the-scenes Grace. That girl, she’s our BFF. This girl? I’ve never seen her before in my life.

Grace has to be aware that every single person at the party is now staring at her and thinking, What’s up with the wacky kid?

But, magically . . . incredibly . . . somehow . . . it works.

Grandpa stops dancing, says something in Aunt Patty’s ear, and disentangles himself from her. Then he walks over to Grace and looks her in the eye.

“Are you okay, kid?” he asks, concerned.

Grace just stands there and stares back at him, until the last notes of the song drift through the air. And then, when the moment of danger has passed, Grace shrugs her shoulders.

“Ha-ha-ha! I was kidding, daddy-o,” she says with a chuckle. “You’re not really my type.”

I look at Luis and we both mouth the same thing to each other: Daddy-o? What book did Grace pull that one out of?

Now that the goofy-girl show is over, the partygoers make their way back to their regularly scheduled activities—pairing up for slow dances, doing cannonballs into the pool, and talking about the Brooklyn Dodgers, of course.

“Dodgers have a six-game lead for first place after that doubleheader today,” someone reports to Grandpa Joe.

“Looks like the Giants really need you,” I add.

“I just hope I get a chance to help,” Grandpa Joe says humbly.

“I think you will,” Luis says slyly. “I just have a feeling about these things.”

Grandpa Joe and Grace stare at each other for a moment. Then Grace laughs weakly and lightly punches Grandpa Joe on the arm.

“Where’s your girl?” she asks. “There’s something I’ve been meaning to tell her.”

Grandpa Joe points Grace in Patty’s direction. Luis and I follow her. We can’t wait to hear what she has to say.

“I’m really sorry I interrupted your dance,” Grace apologizes. “I think I’m light-headed because I haven’t eaten anything yet. And I am definitely going to have to take you up on those dance lessons one of these days.”

“That’s okay, sweetie,” she says. “I understand.” Patty laughs. “Joe is hot stuff!”

Patty has never been one to hold grudges, it seems.

“That’s for sure.” Grace smiles as she glances my way. “Just do me one little favor.”

“Sure thing,” Patty replies. “What is it?”

“Promise me that if you dance with him again, you’ll dance over here, away from the pool. And I know you don’t want to dance on the grass, but there’s another big patch of cement here leading into the house. And look, there’s a lot more room for you to be all whirly and twirly and, you know, ballerina-like.”

“Oooh! I like the way you think,” Patty says.

I stare in wonder and admiration at my friend Grace. Grace—the kid who always shared her crayons with me in kindergarten. Grace—the only kid who didn’t laugh at me for eating paste because it looked just like a can of white frosting. Grace—who, when Ms. Tremt said time travel was powered by positive energy, went above and beyond the call of duty to make sure Grandpa Joe got his chance to be a Major League Baseball player.

“I like the way you think too, Grace,” I say, and we smile at each other. But there’s no time to lose. Because The Book of Memories is starting to glow. We have exactly ten minutes to get back home.