At the beginning of summer, my company lost a dear colleague unexpectedly. This woman was the kind of person who had friends everywhere—at all levels within the business, in all geographies—and it sent everyone into shock and mourning. Fiona had relocated to the US from our UK office but was born and raised in Ireland. During the last decade, she worked mostly in Minnesota, spent a couple of years running our India office, and patched together a wide network of friendships that included coworkers and even clients. During her brief hospitalization and subsequent death, the closest of those friends gathered together with her parents who had flown over from Ireland to help plan her services, settle her affairs and share a decade’s worth of memories, laughs and tears.

At her memorial service, someone referred to these closest friends as the “family Fiona chose” to surround herself with when she was far away from her actual family back in Ireland… and that phrase stuck with me… I think we all do this, to some extent. Even when our actual families are just down the street.

There is an inherent difference between family and friends—at least in my introverted view of the world. While regular friends are a great addition to one’s life, they can invoke a bit of anxiety for an introvert: Do I seem friendly enough? Am I being “fun”? Am I acting like a dork? (Shades of junior high.)

Family is another matter. They’re stuck with me—in all of my dysfunctional glory. If a family member drops by unannounced, I throw open the door without worrying that the house is a mess. If there’s a lull in the conversation, I’m not compelled to fill it. They can see me without my make-up or with a stain on my shirt and I won’t lose sleep over it. We can bicker about something, but I know they’ll love me anyway. Sometimes, however, despite our love for our families, we don’t always share the same views or interests. And so we may not hang out with them the way we would a friend. But when friends and family come together in the same person, it’s a beautiful thing.

I have lots of acquaintances, but I have a smaller number of “friends” and an even smaller subset of friends that I would classify as “family I choose.” But when I realize someone has reached this hallowed status, I try not to take them for granted.

KitKat, for better or worse, has reached this status. We’ve known each other for 18 years and know the ways in which we’re different and the ways in which we’re exactly the same. I can always trust her to “give it to me straight” when I need a dose of reality. At the same time, if I’m anxious or upset about something, I know she’ll say exactly the right thing to calm me down. Since KitKat’s the oldest girl in her family and I’m the youngest in mine, our relationship gives me the chance to be the big sister and her the chance to be the little sister… Because, alas, I’m four years older, I’ve undergone certain milestones first. Both the good (marriage, children) and the bad (turning 50). For all of that, it works well. After all, I’m capable of giving awesome advice (even if I don’t always follow it myself) and KitKat is great at helping me envision a better version of myself.

I’m blessed to have a few other friends in this category as well—and also a couple of family members who I think would still be “chosen family” even if they weren’t already sharing the same last name.

At my colleague’s memorial service, it was clear that her chosen family knew they were special to Fiona. She made a point of living her life that way. Her death was a reminder to make sure my own “chosen family” understands what they mean to me.