They're nearing the end of an early dinner, deciding between a jumbo banana split or three hot fudge sundaes, when Olivia gets the call.

She's sitting next to Elliot on one side of the booth; Noah had insisted, for some reason, on having the other to himself.

"Sorry guys," she starts, releasing a long sigh as she slides out and heads toward the lobby. "I'll be right back."

Elliot can see the change in her immediately.

For the past few hours, she had been weightless. They had stopped at the playground after picking Noah up from school; she'd tossed her blazer on a wooden bench next to Elliot's jacket, letting the afternoon sun wash over her bare shoulders.

It had been Elliot's idea to try out the seesaw, one of the few remaining structures of its kind in New York City.

He and Olivia had raced over to it, Noah recording them on his phone as they took their places across from each other, finding their balance. They had fallen quickly into the back and forth of it, eyes locked, laughing as they bounced and descended and soared.

At one point, he had stopped the motion, digging his feet into the rubber mulch to ground himself, keeping Olivia in the air.

"What are you doing?" she had exclaimed, legs dangling as she looked down at him.

The light had peeked through the trees behind her, silhouetting her frame, and he had tried to memorize it—her soft gaze and wide smile, the catch in her breath as he answered her question—

"Watching you fly."

Now, at the diner, Elliot notices the pause in Olivia's step as she answers the phone.

Her body comes to rest against the front door.

The heaviness lands.

Olivia's job, like his own, is her gravity. In every moment of lightness, it holds her to the earth; it pulls her into the underground.

He knows, all too well, that they've chosen this—a life in the depths.

They've spent their careers mining the world's hidden, broken spaces, listening for voices calling through the rubble, taking hold of every reaching hand.

He knows, too, that they would choose it again, ten times over.

Still, Elliot thinks, as he spies Noah staring at the table, preparing himself for another canceled plan, a new disappointment—

The price.

He decides to distract him with the prospect of ice cream.

"So what do you think, bud? Hot fudge sundaes?" he asks, their blue eyes connecting.

"Nah, let's do a banana split." Noah responds with a smile.

"You got it," Elliot replies, closing his menu.

"Good," Noah begins. "I like when we share stuff, El," he continues, shuffling a few leftover onion rings around his plate. "The three of us."

Before Elliot can say anything, Olivia returns to the table.

"Okay, it's not as bad as I thought. Fin said we should be okay by morning so I can still make the field trip. They just need me for few hours—Velasco's stuck upstate wrapping up interviews and Rollins got sick on some sushi."

"Oh God," Elliot starts; a memory dances between him and Olivia as they both say, in unison—

"You and raw fish."

Noah can tell he's missing something.

"Mom?"

"It's a long story, Noah…" she starts as she searches her phone for another number. "How about I tell you…some bits and pieces of it…on the way to Lucy's?"

Elliot catches Noah shooting a look at him, a silent request.

"Or…" Elliot begins, "and this is entirely up to you, Liv, but what if…" He stands up to whisper in her ear. "What if I drive you to work, grab some ice cream with Noah, and we hang out at my place until you're ready?"

Despite Elliot's efforts to be quiet, Noah can still hear every word. He watches his mother consider the idea, her eyes filling with an emotion he can't quite understand.

This, it seems, is about something deeper than a car ride and dessert.

This is a change, a letting go; this is Elliot, rooted in the ground.

"Okay," she finally breathes. There's a hesitation…and then, a decision. She presses a quick kiss to Elliot's cheek as she gently squeezes his hand, an unspoken thank you.

The rest is a rush—paying the check, making their way to the car, the trip through stop lights and traffic to the precinct, a hug from mother to son, a glance from partner to partner.

She leaves them with a wave as she heads through the doors of Manhattan's 16th.

For a few seconds, it's silent. Different. New.

"Guess it's just you and me, kid," Elliot finally says, turning to Noah.

"Yup," the boy replies, a smile slowly forming. "You and me."

As Elliot shifts the gear into drive and pulls onto the road, his mind starts flickering with a set of memories—

The light of a TV at 3am, the sound of infomercials, watching Maureen drift off to sleep in his arms.

Feeding Kathleen a bottle at the end of a hospital bed, her small hand grasping his pinky.

Sitting up with Lizzie and Dickie, two bassinets beside him, soothing their tandem cries with a tender song.

Holding Eli, the peace after the panic, a few gentle words—

Hey, little man. Welcome to the world.

I'm your daddy.

The first time, with each, that he had felt like their father.

The realization that a bond had been made.

The wheels turn.

Elliot tries not to get ahead of himself but he can't help it—

He looks over at Noah.

He feels it again.