"From Teacher and Student to Brothers"

September 2014

Charlie was standing in his favorite lecture hall. Tomorrow he'd be teaching his first class of the fall semester. Right now, however, he was thinking of when he first taught this class twenty years ago. He couldn't believe it had been that long.

"Happy 20th Anniversary, Professor."

Charlie spun around at his voice and grinned. "Doesn't that make you feel old?"

Reid walked into the room and laughed. "Well, when you factor in that was I was twelve and you were seventeen when we met, you can't technically call either of us old yet. But, we have known each other for majority of our lives now." He stopped in front of Charlie, his hands in his pockets. "If someone would have told me that my first math professor when I went off to college would be the longest relationship in my life outside of my mother, I wouldn't have believed them. But, I'm grateful it is."

Charlie smiled, patting Reid on the shoulder and walking them out of the room for a trip around the quad. "If someone would have told me that I would have had a student that became like a brother to me, closer to me in some ways than my own biological brother, I wouldn't have believed them either. But I'm also grateful."

The pair meandered around the quad, remembering their times together while Reid was in school – his vending machine hack, the boat race, when they went to San Francisco for a conference, when they helped Larry with some of his presentations…

"You know, I think some of our best work was when we were no longer teacher and student," Charlie commented.

Reid smiled. "I agree. This past decade, in particular."

Charlie nodded. "Yeah, it's been a crazy ten years, but look at us now. Both top of our fields, although different—"

"And yet similar. Both of us study math and the brain. Yours just looks at how math runs the brain, creating our behavior and I look at how behavior uses math without even realizing it."

"True. Both of us married and with a kid," Charlie grinned. Charlie and Morgan had been co-best men at Reid and Maeve's wedding a few months ago in Vegas. Charlie had been incredibly thankful that they got that moment after Spencer's scare in May. If he hadn't had his family, Amita and Matt in particular, he could've easily spiraled down into some tangent like P vs nP or something like Posdner again when he had gotten the news that Spencer had been shot in the neck and nearly died at the hands of a corrupt police force.

"That really is the miracle here," Reid added. The teacher shoved his student some, getting a laugh.

The pair settled on one of the outside tables with a chessboard set up. Students often played each other between classes. The geniuses were no strangers to the tables themselves. They quietly began a game.

"Thank you Charlie."

The older man looked up from the board, "For what?"

"For being my teacher, my mentor, my friend. For becoming my brother. I don't know if I would have made it through these past twenty years without you." He paused. "Well, I probably would have, but not nearly as well. I have Maeve and Yeong now and my team is my family, but before that, I had my mother and I had you. So thank you."

On his way to campus, Reid had reflected on Charlie's impact on his life the past two decades. He had helped him though his college years, had really given him a support system he hadn't ever expected when he went off to get his higher education. But, it was ironically his help after he was no longer his student that had the biggest impact. He helped him navigate those early years at the FBI when he hadn't or couldn't fully open up to Gideon, Hotch, and Morgan. Then later JJ, Garcia, Elle, Emily, Rossi and Blake.

As close as he was with his BAU family, there were just some things Charlie could relate to that the others couldn't. Having that man just a phone call, and sometimes a short flight, away was an anchor that helped him through the dark moments in his life like the Fisher King, his abduction and addiction, Gideon leaving, and Emily's death and resurrection. He was also there to help him process the happier moments like becoming a godfather, falling in love, and becoming a father. He couldn't fathom how he would have gone through all of these things if he didn't have Charlie in his life.

Charlie grinned. "Well, you're welcome. Thank you as well. You've helped me just as much as I've helped you Spencer. I may have been the teacher in title, but I think you've taught me more about life than I have for you. So thank you."

When he had entered that classroom, before Spencer had announced himself, the mathematician had been reflecting on the same thing. It wasn't until his work with the FBI that Charlie got close to Don, and Spencer could take some of the credit for that. Spencer had helped him process moments like Larry's space expedition, Ashby, DARPA, Posdner, and Amita's kidnapping. He'd also been there for when he finally moved forward with his relationship with Amita, his London trip, and the birth of his son. Even though he was now very close with Don, Spencer just related to Charlie in many ways more than his flesh and blood ever could.

Something about being child prodigies, something about that shared genius, that kept the pair forever linked – forever bonded. Neither knew where their lives would take them from here, but they knew there would be ups and downs. What they did know, even if there was no mathematical equation to support it, was that they could count on each other to be there, no matter what that future would be.

Because that's what brothers do.

The End

A/N: I know there are things in seasons 10 & 11 that Charlie could help Reid through. But, so could Maeve in many ways. The story was becoming too one-sided for me as I was struggling for a good balance, outside of happy news, on Charlie's side. I thought of creating sad news, but didn't have the heart. At least I made Reid's life a little happier with Maeve and then Yeong. When I could see that I was reaching the end of my creativity for this story, it seemed fitting to end at the beginning of season 10, making the story have run over ten years. I'm quite pleased with this ending; content to leave "Shared Genius" at this point in time.

Thank you to all that have reviewed, followed, and favorited this story. I would especially like to thank some loyal readers that also constantly took the time to review this story - ahowell1993, mabelreid, and Sue1313.

When I started to rewatch Numb3rs, I hadn't expected this to come from it...or the creativity resurge that came with it as well; it really can take credit for anything I've posted in 2015 and beyond. So I thank that great show, which was in many ways was also the start of the "nerd" character becoming cool. Charlie really can take at least some credit for characters like Reid, Dr. Brennan, Hodgins and the squinterns from Bones, Chuck "Carmichael" Bartowski from Chuck, and the whole gang from The Big Bang Theory becoming key figures on our television screens.

Anyway, thanks again for your support! ~Ann Parker