It doesn't feel like she leaves the precinct for the first week. Two nights she literally sleeps in the break room, even after the FBI packs up and goes home, even after Esposito continues to mutter under his breath about the video, even after everything. The other nights she gets back to the loft, which is dark and quiet in the middle of the night, and doesn't see either Martha or Alexis before she leaves again before the sun is up.

But it's when Gates apologetically shuts down the investigation, the time and resources it is using that she realises she'll need to go back to her apartment, at least part-time.

Alexis catches her packing a few clothes.

"Kate…are you leaving?"

She turns slowly to face the younger woman. Anger threads Alexis's voice. Anger and fear. Pain too. Denial. A thousand other complex emotions, ones she couldn't give a name too, but ones she has lived through herself.

"Alexis, no-"

"I can see you're packing. Leaving because don't think Dad's coming back? That's it, isn't it? You think he's dead."

She knows Alexis is angry, lashing out, but each of those words are like body blows to her, buffeting her. Angry blue eyes peer out at her from under orange hair, twin to his own, so much so that looking at them is painful in its own right. But right next to that anger is the shimmer of tears.

She doesn't have the words, but she doesn't need them. Instead she reaches out for Alexis, for one of the few people who is feeling as rocked and torn and distraught as she is, and encircles her in her arms.

"Alexis, I would never."

At first, she feels the younger woman struggle, but she injects her words with the simple faith of her absolute unwillingness to give up this fight.

"I will never, ever give up on Castle. He will come back. But I just need…"

"Stay."

"I will, I will stay. We all need to be here for one another, you and me and Martha. But they're shutting down the investigation at the precinct. I need to go to my place so I can keep investigating, keep chasing leads. Set up my own search."

Alexis steps back from her, trembling fingers wiping the tear tracks from her eyes. She lets her find her own strength, her own resolve, knowing how important that can be.

"And you can't do that here?"

"I think it would be best, for all of us, if I didn't. But I'll come back here most nights, and I'll keep both of you up to date with whatever is happening, I promise. You'll get all the answers."

She knows how important that is. She's lived through that.

Only this time, unlike when she was Alexis's age, there's going to be a happier ending. Castle will be alive. She's going to find him.

For all their sakes.

A/N: Prompt was for Kate and Alexis interaction in the wake of Castle's abduction, something the show chose skip over (and was immensely weaker for, IMO)