As I’m helping my little sister settle in to her new place here in Lexington, far from our southern California nest, it’s hitting me: adult sisterhood has, ever so slowly and without warning, crept up on us.

There are two stages of sibling-dom.

The first is when you live under the same roof. Maybe share a room or a bathroom. The kind where you’re constantly screaming at each other, for not asking to borrow a blouse, for crashing the sleepover, uninvited. When all you want is to be far away. When all you want is space.

The second is when adulthood creeps into the scene: jobs, opportunities…just life. It means that a member of the species that used to be considered cooties-infested, is now a significant other, and you have to share her with him. It means you live in separate places, separate cities. Sometimes separate countries. In this case, separate states. When all you want is to not be so far. When you’d give anything to remove that space.

It’s right now that I’d take being 8 years old, fighting over a headless Barbie doll, over the thought of being 25 years old, looking back at her through tear-fogged eyes as I leave her at her in Lexington airport, Los Angeles-bound. Because one means that home is in one place, in the same place.

That feeling of permanence is hard to escape. The void you know that you will face is heavy, and can’t be replaced by texts, emails, phone calls or even Skype.

But life goes on, it has to. And though a lot must change, some things never do.

“A sister is a little bit of childhood that can never be lost.”