It was late when Rick finally opened his front door, and his first stop was to go check on Alexis. No matter how many times he had told her she could wait up for him when he stayed out late- in fact he might have preferred she waited up for him to get home- she was always in bed at a reasonable time. He sometimes wondered if his ex-wife hadn't given birth to an old woman.

When he got to her hall, a light could still be seen shining under the door. Castle frowned. Alexis didn't stay up this late, even when she had a big test the next day. When he opened the door, his heart beat faster, a ball of acid suddenly burning in his stomach. His daughter's bed was empty.

He remembered he used to be able to find her in his room, though the last time she'd slept in his bed when he was out was several years ago.

He made a mad dash down the stairs and scrambled to find the phone. He rushed to snatch the phone off the dining room table, hit the button and held the device to his ear. As he listened, he heard a very familiar little sleep-snort almost obscured by the dial tone.

Rick hit the button again, and stood still for a moment, willing his heart to slow and his breathing to quiet. As he held his breath for a second, he heard two very gentle intakes of breath, one the familiar hitching breath of his daughter.

Rick slowly moved around the couch, surprised and touched to find his daughter curled up on the couch, her head snuggled on the shoulder of Detective Kate Beckett.

As he watched, Kate stirred, reaching up to scratch at a spot on her cheek that had been seconds before resting on his daughter's hair. Kate yawned and frowned, her free hand coming up to rub her neck, and Alexis stirred then, nuzzling her face into Kate's shoulder and wrapping her arm around the older woman's waist, then immediately falling back to peaceful rest.

Kate suddenly felt the presence of someone nearby and her eyes blinked open to find Castle standing over her with a sentimental look on his face. The throbbing ache in her shoulder reminded her that the look was probably caused by the cuddly teen curled up next to her. She couldn't really recall how the two had ended up like this, but it had been an effortless kind of comfort she felt around the teen. Kate could easily see why her father was so proud of her. She was smart and strong and yet completely endearing and innocent. And a heck of a lot of fun.

"Good morning, sleeping beauty," Rick teased, keeping his voice low so as not to wake his daughter.

"What time is it?" Kate asked, ignoring his comments.

"Just after two."

"Slinking home from something scandalous?" she teased.

"Wouldn't you like to know," he teased back.

"No, actually, I wouldn't."

He just chuckled, not convinced. "You gotta be careful around this one," Rick said, gesturing to his daughter. "She invariably ends up curled around the warmest thing in the room. Usually that's me, but in this case, obviously it was you."

Kate smiled, but tried to hide it from Rick. "I guess we should get up to bed," she decided, using the arm around Alexis to shake the girl gently until she stirred. "Your dad's home. Time for us to get to bed," Kate told her, gently trying to wake her.

"I got her," Rick said, then picked up his nearly grown daughter, and grunted. "This was a lot easier when you were eight."

"You didn't have to carry me, dad," Alexis mumbled as he walked away with her in his arms.

"I was trying to impress Kate. It's not my fault you're so big! If it were up to me, you'd still be eight!"

"I'm not big," Alexis complained.

"For an eight year old, you are!"

She barely shook her head, too tired to continue the inane conversation. Kate watched them as Rick made his way upstairs, carrying his daughter. He made it to the first landing, then had to set the girl down, his arm wrapping around her shoulders instead as he continued helping her up.

"She's all tucked in," Rick said, seconds later, coming back down the stairs. When he met Kate on her way up, he blurted, "Where are you going?"

"To bed," she said, using a 'duh' tone.

"Oh," he replied, obviously disappointed. "I thought… we could share a drink or something."

"I have to get up early," she said, moving around him to head up the stairs.

"But it's Saturday."

She turned back on the first landing and tilted her head in annoyance. "Haven't you noticed, Castle? I get up early every day."

He just wrinkled his nose in distaste, then said, "Until tomorrow, Detective."

"It is tomorrow," she called back, already moving up the stairs.

"Kate," he called in a different tone when she was on the top landing. When she turned back, he was looking up at her, smiling gently. "Thank you for spending time with Alexis. She won't admit it, but she hates it when I leave her alone. And she really enjoys spending time with you."

"It was no problem," she said, trying to remain aloof, until she thought about the night and the girl she'd spent her time with and she smiled too. "She really is a great girl."

"Well, I think so. But then I get accused of being biased, so I usually just let people figure it out on their own."

Kate just smiled, humoring him a little, then went to her room.

Settled up in her own bed, Kate realized she couldn't continue shutting Alexis out of her life. As long as she lived in the loft, Kate was going to have to include the girl more in her everyday routine. It wasn't fair to ignore the girl when it was her father Kate was actually trying to avoid becoming attached to.

But as she thought about it, Kate realized it would not be as big a sacrifice as she made it seem.

Alexis really was a lot of fun to just hang out with.