A/N: This one- shot just sort of came to me, because I always liked the way Magnus interacted with the Infernal Devices characters. Magnus and Jem don't have a lot of interactions in the books, but I like to think that they're friends, or at least close to being friends.

Magnus sat in his hospital bed, writing furiously in his notebook.

He was still weak and tired from the ordeal with his father, but he had to get this done, for Alec. Alec had literally gone to hell and back for him, and so he owed it to Alec to do this. He scribbled like a madman, writing down things that he hadn't talked about, or even thought about, in years. He was writing so furiously that his fingers cramped. He sighed and put the pen down, shaking out his hand. That's when he saw someone who he hadn't seen in a very long time.

"Jem?" He asked. The shadowhunter turned and smiled at him. "Hello Magnus, long time no see."

Jem looked like he was almost the same age as he had been when he had become a silent brother. But now, instead of a skinny boy with silver hair and eyes, he was a strong, built man, with dark hair and brown eyes. And even though he looked young, those eyes were full of wisdom that only came from being alive for a long, long time. It was a sort of wisdom that Magnus recognised from spending so much time with people who were immortal. James Carstairs was much older than he looked.

Magnus laughed breathlessly. "How?" He asked. "Jace's heavenly fire." Said Jem, "You know, it sort of figures that it was a Herondale who did it, I already owe that family so much." Magnus raised his eyebrows, "You owe them?" Jem nodded and Magnus laughed again, "You three are adorable." Jem didn't ask who "you three" were. It was obvious to anyone who had known him, Will, and Tessa, that they were three of those connected people in history.

For his part, Magnus was coming to grips with the fact that Jem was back quite quickly. It had been unexpected to see him in his hospital room, but he had actually had a dream that Jem would be returning. He was glad that it had come true. James was a good person and he deserved to have a good life with the person he loved. Speaking of which, "What are you doing here?" He asked.

Jem fidgeted, "The silent brothers wanted one last check up, to study the affect of the heavenly fire on the yin fen, but then I'm going to leave, and go…"

"To Blackfriars Bridge?"

Jem's head shot up, "How did you know?"

"Darling, Tessa lived with me for years. Did you really think I wouldn't notice? I mean, the first year she stayed with me, she was so broken up over Will's death that she cried herself to sleep every night and woke up screaming. She even tried jumping out the window a couple of times. I have never seen anyone so completely destroyed in all my life. Then suddenly, one day in december, she left the house for the first time since she had arrived, and when she came back she… She wasn't happy, not by a long shot, but she was no longer completely suicidal. That night she slept soundly for the first time I months."

Magnus shook his head, as if he still couldn't believe it, "Every year it kept happening, she would leave one day, and come back… revived. So one year I followed her, and it all made sense."

"You followed her?" Asked Jem suspiciously. "Just to the bridge." Magnus assured him, "Once I saw where she was going, it all fell into the place, I really should have figured it out sooner. I didn't spy on your date, and I didn't tell her that I knew, nor did I tell anyone else that your weird little romance was going on. I just wanted to see what was helping her, because none of my normal grief tactics were working."

"It wasn't really all that romantic." Jem protested, "I mean, I was a Silent Brother."

"But you love her." Said Magnus. Jem sighed, "Obviously."

"And she loves you."

"Well…"

"Oh come on James!"

"What do you mean 'Oh come on James'? I know she was in love with me once, but that was over a hundred years ago! How do I know she still feels the same way?"

Magnus sat up in exasperation, "Have you not been listening to me? For years she was a mess, and the only thing that kept her going was those dates- or meetings- with you! She lived for the one hour a year that she got to spend with you, outside, in public, as a silent brother, they were what kept her from going completely insane, they were her reason to live. If that isn't love I don't know what is."

Jem looked at him sadly, "I hope your right. I barely know how to function now that Will is gone, I don't know if I could bear it if I lost Tessa too."

Magnus gripped his notebook tightly, "I know what you mean. I feel the same way about Alec."

"Yeah, you really need to explain to him that you weren't involved in a passionate affair with my parabatai." Said Jem, snickering a little. Magnus glared at him, "I think I liked you better as a silent brother."

"I'm sorry, but it is a little ridiculous that all these people think that you were screwing Will."

"Didn't you have a doctor's appointment to get to Vivaldi?"

"Did you just call me Vivaldi?" Asked Jem. Magnus shrugged, "You play the violin, it was the best nick name I could think of." Jem just laughed, "Goodbye Magnus." He said, walking towards the door. "See ya later, Vivaldi." Called Magnus, waving.

There was a pause.

"Oh and Jem?" Said Magnus. "Ya?" Asked Jem, turning around.

"Good luck with Tessa."

"Good luck with Alec." He replied. Then he left, and Magnus went back to writing in his book with renewed vigour. If James Carstairs, a sick orphan with a cursed Parabatai, an addiction to a demonic drug, and a fiancé who was in love with his best friend, could have a happy ending, then so could he.