I signed up at fanfic50 to do 25 jack/chase fic (I've always wanted to do that). So, here's the first one :) And the prompt table is to be found here

She had never taken it seriously, not really. A harmless crush, she’d thought, a passing fancy that made him smile, which was great to see. And even when his bed had definitely been untouched two or three mornings a week she hadn’t reconsidered. A one way attachment, and hopefully he wouldn’t hurt for too long when things ended.

But then she had witnessed something that made her change her mind.

It had been a particularly difficult week. Angela had been sick and crying for three days, Helena was out of town as was the babysitter and Chloe had barely been home because CTU was insanely busy since the threat level had been raised. She knew that Chase probably hadn’t slept more than two or three hours a night for at least five nights in a row and she knew how difficult things still were for him with his arm. The wound was healing slowly but he still was in pain and she guessed that it didn’t really help that he was being left holding the screaming baby. But as much as she hated leaving him to deal with Angela and his handicap all by himself she couldn’t get away from work.

When she came home after another 18 hour shift on Sunday evening she could barely stand upright and was as tired that it made her nauseous. But when she had kicked off her shoes and turned to great Chase she found him looking even worse. She could tell he was on the verge of tears, Angela crying and kicking in his arms in discomfort and his eyes almost as red as hers.

All she wanted was to crawl into her bed and pass out of complete exhaustion but it hurt her to see him like that and without another thought she reached out to take Angela from his arm. But he just shook his head tiredly.

“Go get some sleep, Chlo” he said softly.

"But you..."
He shook his head once more.
"Even your brain needs sleep" he said with a weary smile.

She was too tired to argue, feeling tears well up in her eyes as well. But before they could spill there was a knock on the door and when she opened it there was Jack, looking just as tired as she did, and there was a huge bag of groceries and a tired smile. Without further ado he stepped past her into the hall and set down the bag before turning towards Chase and, ignoring his weak protest, taking Angela from his arms. He settled her onto his hip and reached out with his other arm, pulling Chase into a tight hug, offering the much needed comfort without a word. He held him for a long moment, while he rocked Angela in his arm. Then his lips found Chase’s temple in a soft kiss and Chloe could hear him ask. “Why didn’t you call earlier?” There wasn’t a hint of reproach in his voice, only concern, unmasked. And understanding. And Chloe fleetingly wondered where all that strength came from. He’d been working more than she had, slept less, eaten less, if at all, and still there he was, solid and calm and comforting. And frighteningly private.

Chase didn’t answer, couldn’t answer, exhaustion finally getting the better of him silent tears now streaming down his face and Jack simply continued holding him, running his hand over his back in comforting circles. “It’s okay, I’m here now” she heard him whisper and felt herself unable to move, completely taken aback by the tenderness of Jack’s expression. Tiredness flooded through her body and she just stared at the scene in front of her, allowing herself to draw comfort from Jack’s presence, too.

When Jack lifted his head and looked at her she snapped out of her thoughts, slightly embarrassed, but his smile was reassuring. “You look as if you’re falling asleep right here, Chloe. Go get some rest.”

She felt herself nod, and squeezed past them on her way to her room. The last thing she heard was Jack’s voice, that gentle, soft voice she had never heard before. "Why don't you take a bath? I'll try to calm Angela and make some dinner."

When she later returned downstairs to grab something, anything, to eat on her way to bed she found a plate with pasta with a note to it, displaying her name and the three of them asleep on the couch. Angela rested on Jack’s chest and stomach and he had protectively wrapped one arm around Chase who was curled into his side. All three looked exhausted but serene. Smiling to herself Chloe switched off the lights and covered them with a blanket, softly kissing each of them goodnight.