No one talks about the loss that happens when you become an aunt. No one talks about what you lose. What you didn’t intend on losing. No one talks about it.

Having a sister, for those lucky enough to have an environment for that relationship to flourish, is a built-in best friend. As cliché as that sounds, as that really is, it’s true and it’s a source of great comfort. A sister is a built-in you’re always there and I’m always there for you, too, no matter what. Grade school friends, they come and they go, they crush on the same boy as you, one fight on the swings, one summer not seeing each other, not sitting next to each other, and your friendship is done, take back the bracelets.

High school friends, they dissolve, too. The same problems really, except your crush is your boyfriend, the swings are traded for the basement parties, and the summer is spent trying to find yourself with the cool crowd, and then you go to different colleges and you’re different, the friendship is over.

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College, that friendship usually lasts a few years, until you graduate and you’re lucky if you stay in contact even on birthdays because life comes fast and you’re learning what the real world means outside of Friday nights, dorm room drama, and college exams. I won’t even get into friendships as an adult because that . . . that just feels impossible.

We lose a lot of friendships in our lives, but what we don’t lose, if we’re lucky, is our sister.

Sure, we can have the same fights, but there is this understanding of hey, I’m still here even if I can’t stand you, even if you annoy every ounce of being inside of me, I still love you and I have your back. Sisters are this gargantuan gift, and one we really are able to see as a present in the present of adulthood. Having a sister now as an adult is a whole new level of appreciation. A phone call when we jam a whole philosophical life into an hour-and-a-half conversation late at night, or random text of encouragement followed by an inside joke about our dad.

It’s this bond, it’s this love, and at any given moment, I know my sister will be there, and I’m there for her, too. I will never lose that connection. I wondered if this would be tested when my sister got married. All the festivities for the wedding made us closer, we laughed until we cried, we dreamt of the day, and I found true joy in the happiness she found by finding her new, life-long best friend.

Now, we just complain about her husband and the way he loads the dishwasher all wrong or the way he couldn’t possible annoy her more with the way he chews or his mess (and then I just remind her of her childhood room and the way we could never see her floor).

It didn’t really feel like I was losing you because after all, she still really needed me and of course I needed her.

Having a married sister wasn’t really that different, it just gave us more material. We grew together, and I was still built-in and she was, too.

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But then, she started talking about having kids. I encouraged it—we talked about how cute they would be, how funny and adorable they would be. The type of mother she would be and the kind of aunt I could be. Then the day came and she told me, “We’re pregnant” with a look of fear in her eyes. I quickly assured her in the excitement and newness, that this was normal, the feeling of fear was normal. We talked all night and she fell asleep.

And then, I looked at her and I felt a feeling of fear. It felt different than any other fear I had before, I couldn’t pass it off as normal. I’m just the aunt—what’s this fear? I shook it off and just blamed it on my ego trying to shine through and compare my single life to your successes. Comparison is the thief of joy, I muttered to myself. That worked. It became my mantra.

Until the next day and the next, and the perceived fear grew deeper. A few weeks had passed and we were having a conversation with our mom, and for the first time, I felt like an outsider.

Like a member no longer invited.

I tried shaking it off again, repeating my mantra. Then, our phone calls became accentuated on her excitement over this new life coming and I loved it, I loved talking about it and hearing about her experience. But at the same time, the fear crept in. The calls became less frequent, she was busy with the changes. My fear, or what I thought was fear, became more persistent. I still blamed my ego. I found myself in moments I wanted to share with her, a quick call to vent, but all of a sudden, I didn’t want to bother her. What? Bother her? That used to be my favorite thing to do. That was our love language.

A few more weeks passed and we were together again. I walked into our parents’ home and she was sitting at our childhood table with her husband and our parents. I heard so much happiness as they all had joy in looking at the black and white outline of this new being I already loved. I felt like an outsider again. And the fear felt more like sadness. I stood there for just a second and all I could see and I could feel was this sense of loss. This sense of transition and change.

And it didn’t feel exciting anymore—it felt like I was losing something, that we were all losing something.

Just like that Thanksgiving, Christmas, phone calls, family dinners, all became sources of sadness. They all became these events in my mind, in my perspective, of things ending, as little reminders that life would never be this way again. That I really needed to cherish this moment because change was coming, and instead of seeing that as a positive thing, it was sad, really sad.

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I found myself disengaging and rooting myself in a fear I hadn’t known. As an outsider looking into a story I’ve read but with an ending I wasn’t expecting. Why couldn’t I just see we were changing chapters? Why could I only see this as the rewrite to a book I no longer felt a part of?

She is now a mother. She is now part of a club I don’t belong to. I may never belong to. I may never want to belong to. She now has this new built-in family—built-in literally with my nephew, intertwined in love with her new family. I feel that joy for her and that’s the way life is supposed to go, right? I mean, I feel underprepared for this sad feeling, and I feel selfish in the sadness of the loss.

But in her gains is a loss. Our sisterhood, those late-night phone calls and texts and days laughing are going to be replaced with her new built-ins, the way it should be.

I think I just need a moment, a moment for this underprepared feeling of losing. I’m not sure how it was supposed to feel, to become an aunt. I can’t wait to see this baby I already love, I can’t wait to see who he’ll be, but I know, for now, I’m a little sad in the joy. And maybe that’s OK.

I never got to say goodbye to that sister I once knew, and I can’t help but feeling like I was so intensely underprepared because no one talks about the loss that happens when you become an aunt. No one talks about what you lose. What you didn’t intend on losing. No one talks about it.

Let’s talk about it.