Author's note: First of all, a million apologies to all those who've been waiting for the final chapter of this story. RL interfered with a vengeance just as I was about to finish it, and then my inspiration went as well (helped in no small measure by how this storyline played out on the show). For those of you who wrote to me to ask me how the story's going, thanks so much for your patience.

You may want to read the story again, just in case this final chapter takes you by surprise. Oh, and a brief warning – this may be a little unusual, but please bear with me. Science all the way, remember? Right? Well, you tell me. :)

She is in her lab when she gets the missing pieces of the puzzle. The catalyst. The cornerstone that holds everything together. Or any other clichéd analogy that her writerly imagination can come up with.

She is not doing anything that she has not done before (a gazillion times before, Booth would say, and she would point out that 'gazillion' is not a word). She is examining a body while testing the intern of the week on prophylactic approaches to rheumatic fever and the effects of said fever on the joints. Something about the conversation rings in her head for the rest of the day, making her increasingly frustrated that can't pinpoint it with precision.

With the perfect timing of genuine friendship, Angela delivers the final – as it turns out, visual – element for breaking the tightly wound knot she's been contemplating all day in the knowledge that just taking a sword to it would probably be useless. It's a drawing of her and Booth at the Jeffersonian party several weeks before. Breath caught in her throat, Brennan looks at it for so long that the artist begins to think she's done something wrong. Just as Angela is about to start apologising, Brennan thanks her in a whisper and gives her a gentle hug, then disappears into her office.

Booth must have noticed she has been distracted all evening. Very little about her usually escapes him, and she surmises that today would be no exception.

"What are you thinking about?" he asks as she's sipping her wine.

Tonight, she's curled in a corner of the couch in his apartment. They've spent almost every night together since their world flipped crazily upside down only two weeks ago. He is next to her, long legs stretched out towards the coffee table.

"Causality is the cement of the universe."


"It's also a habit of the mind. 'Cause' and 'effect' aren't intrinsic properties, they can't be determined a priori. The connection between them isn't there independently of the subject observing it. Instead, causality is part of how we experience the world. As a scientist, I should've remembered that."

Booth's raised eyebrows prompt her to go on.

"I thought that the cause was that I wanted a child, and the effect that I wanted you. I was wrong."

" were?"

He does not trust himself to say more.

"It's the other way around. You and I are the cause. Everything else.... everything else may or may not happen, but there's no way to know beforehand. All that I know is that we come first."

He looks at her, head tilted, a faint smile forming on his lips.

"You sure?"

"Yes. It fits. We fit. We're the center, remember?"

He gets it. He always does.

"And the center will hold."

He scoops her up and spins her around until she's dizzy. Finally, he listens to her weak protests and sits down with her curled in his lap. He doesn't let go for a long time. Neither does she.

A gazillion kisses and a heated make-out session later, he grins at her.

"Pretty good explanation, Bones. Even for a philistine like me."

"You know that I learn from the best."

He stifles the mandatory cheesy comment and goes for the practical demonstration instead.

Biological urges, anthropological inevitabilities and scientific truths tossed aside, here they are, lying in bed, the faint light from the street filtering orange through the half-drawn drapes.

She's almost asleep when she hears him speak.


"Yes", she mumbles a little indistinctly.

"Do you want to have a baby with me?"

"I do."

She wonders for a moment why the words sound solemn, as if she's saying them in front of an altar in some ancient ceremony, the two of them the only participants.

Her head between his neck and shoulder, his arms around her, they sleep.

And here we come to the end of the journey (and to the lovers' meeting, as Angela or Shakespeare would put it). Before you start throwing things at me for leaving it somewhat open-ended – I think this is where they should be in order to start 'evolving' together.

For this fic, I set myself the challenge of delivering a believable 'B/B get together' story where Brennan decides to have a child without surrendering to the temptation to include any any of the following: Brennan suddenly surrendering to her biological clock and deciding to use Booth instrumentally for that (because that's not what people who are in love do) – on this point, I should mention that I started to write with this idea in mind long before Critic aired; Brennan exploring the IVF treatment and sperm banks route (why would she do that, anyway?); any of the many ways in which Booth would say 'no' to her request (because it is much more interesting if he says yes – plus, let's face it, he does want to have a child with her if he's really honest); a much too interfering Angela (she can be such an irritating little shipper sometimes – I prefer to see her as a good friend); I won't bore you with the rest of the things that I tried to avoid.

But the bottom line is that I really think that asking someone to have a child with you is a way of to saying 'I love you'. Even for Brennan, even if she doesn't know it at first.

So... how did I do?

Please tell me by reviewing one last time. And thanks for reading!