So, I found this on my drive and decided to just put it out here.
I guess you could set this anytime during season 5 or 6. Hope you like it.
He arrived that evening and found her on the couch, wrapped on an old blanket she said she would never get rid off. It had a few holes on it, but she'd said it had been a gift from her grandmother that her mom used to wrap her when she was born, so the blanket stayed.
He hadn't seen it since they unpacked her things when she moved in.
"Hey" He said, pulling her out of the trance she was in. She looked up and he noticed that something was off. The lights were dimmed but he could see that her eyes were red-rimmed, make up ruined and a few tissues on the ground. "Kate, what's wrong?"
He made his way to her not missing a beat, holding his breath. He noticed the mug on the coffee table, steam still rising from it, so she hadn't been camped out here for long.
He kneeled before her and ran a hand through her hair, making her look at him.
"Kate, tell me what's wrong" He pleaded, eyes locking on hers.
She covered the hand he had on her cheek with hers and smiled. She felt him sagged in relief at seeing her do so, but his eyes still held some hints of worry in them .
"Everything is fine" she said, a flash of uncertainty passing through her eyes. "Well, I hope everything is fine."
"You hope? Wait, it's way too early for you to be home. Did you guys close the case already?"
"No. Gates sent me home. I wasn't feeling very well"
"Are you okay? Do I need to call a doctor? Are you hurt?" he stood up as he went on rambling that she should've called him while looking for his phone. She bit her lip and stood up, grabbing his wrist to stop him to make any calls.
"Castle" he still wouldn't shut up. "Castle, shut up!" she covered his still moving lips with her hand, his eyes widening all of the sudden. "Are you going to stop talking?" He started answering her but the glare she sent him shut him up and he just nodded. "Good, 'cause I have something to tell you and I need you to just listen for a second, okay?" he nodded again and she dropped her hand, taking one of his instead.
"As I said, I wasn't feeling very well today. Everything was making me nauseous." she wouldn't meet his eyes, her eyes focused on their hands. "I came home and I was going through the medicine cabinet looking for something to make me feel better when I noticed something that got me thinking..." She looked up to him then, her eyes watery but smiling.
She turned and leaned to pick up something from the couch, hidden under the blanket. She held the stick up, smile growing as she said the words. "I'm pregnant, Castle"
She watched as his eyes moved from hers to the stick in her hands and back, stunned look in his face, and she started to worry. "I now that we actually never talked about kids before, hell we're not even married, but I have always thought you wanted to..." she drift off as his hand slipped from hers and came up to grab the pregnancy test she was moving around while she was talking.
He stared full into it, no saying anything, and she started to fidget, worrying her lip once more. "Castle, please say something" she pleaded.
He looked up to her then. "Kate" he breathe her name as he pulled her in and kissed her deeply. "Kate" he said again when their lips separated, foreheads touching. "Kate, is this real? Are you really pregnant?"
"Yeah, I am" she felt his arms tightening around her.
"And you're okay with this, Kate?" He moved away, needing to see her face, her eyes.
"I might be a little be scared" she paused, taking a deep breathe. "But I'm okay. I want it. I want to have this baby, Castle. Our baby. I'm happy."
"Our baby" he whispered as leaned back in and kissed her.