Once my brother and I got past elementary school, we stopped having petty sibling arguments and became best friends. I’m not exactly sure how, but my parents made sure we got along — and I couldn’t be more grateful. Getting along with my brother in the way that I do has helped me through life in many unexpected ways. Most importantly, it’s ensured that I have always had a best friend at my side. Brother-sister duos like this can be rare, but, from my experience, the they usually have these traits in common.

1. You know all about each others’ interests, and have even adopted some of them yourselves.

People at school know me for my love of music, farm animals, and desserts — all of which I’m very vocal about. What they don’t usually expect is that I also have over 100 hours logged in Skyrim and can recite the current Detroit Tigers lineup. Likewise, this past spring I was assistant music directing the show Legally Blonde at my high school. After telling my brother this he decided to watch the musical himself, and a few days later I woke up to these texts:

My brother really likes video games and sports, and I really like music and theatre. But our interests aren’t mutually exclusive. In fact, because we’re so close, our interests have kind of blended together. You wouldn’t believe how much this has helped me make new friends and find common ground with people I wouldn’t usually have been friends with otherwise. And it's the same for my brother: one of the first texts he sent me about his now-girlfriend was about how they were bonding over a love of showtunes and movie-musicals.

2. You both know how to talk to people of the opposite sex.

When I was in middle school, this “skill” was literally the envy of all my friends. I had played the zombie mode on Call of Duty: Black-Ops with my brother one time, and it was like I had a free pass to talk to all of my friends’ crushes without being judged. Totally weird, I know, but very beneficial when middle-school-me played wingman.

In all seriousness, my brother and I grew up with friends of the opposite gender because we knew how to talk to them like people, not like solely love interests or aliens from another planet. This widened our friend circles and, again, allowed us to get to know people we wouldn’t have gotten to know otherwise.

3. A night in is its own breed of party, as long as your sibling is home.

Okay, imagine living with your best friend. (Maybe you do!) That’s what I’m getting at here. I used to think I was really introverted because freshman and sophomore year I would want to go home and read a book while my brother played video games instead of go out with lots of friends. Now that we’ve been separated by college for two years, I realize that when I was a kid it was just more fun to be around my brother than to go out because he was my BFF.

I have vivid memories of us sitting in the same room, doing our own thing, only breaking the silence to show each other a good meme or ask if the other wanted food. I also remember times when we would just goof around and talk about our respective days over microwave meals.

4. You make fun of each other mercilessly.

When my brother is home from school, he and my boyfriend gang up on me and tease me until I’m near my wit’s end. I’m pretty sure they take bets on who can make me cry faster. Of course, I know it’s all in good fun — after all, I send my brother pictures of his awful circa-2009 Justin Bieber haircut from middle school at least once a month, just to make him cringe.

The key part to this is that you also know which buttons not to push. Unlike siblings who don’t get along, the teasing is earnestly meant in jest. When one person inevitably goes too far, they know what to do to make things better again and then move on — which is the true mark of a best friend.