All siblings make their share of mistakes. Whether it’s misplaced borrowed items or getting drunk at their wedding and embarrassing them. We all do it, no one is impervious to error. The mistakes, like errors, are meant to be learned from not repeated.

I’m human which means I’m prone to faults. I’m going to mess up, it’s a fact of life I’ve dealt with for 30 years. I’d like to say I’ve grown a lot as an adult and I make fewer mistakes now than I did as a teenager but sadly I’m still making slipups.

To fully understand the mistake, I made with my sister, you have to understand our background. My sister and I are nine years apart, which means for the majority of our lives, we’ve been in separate places.

I graduated high school when she was in middle school and I got married when she was twelve years old. I missed the majority of her middle school basketball games because I was well into being a typical teenager. Our relationship has never been an archetypal one. We fight like cats and dogs and we can go weeks without talking.

Kim, my sister, is everything I’m not. She’s tall (I’m freakishly short), she loves bright colors, (my favorite colors are black and gray), she’s athletic (I’m uncoordinated) and she can’t carry a tune in a bucket (I can bring the house down).

Despite all of our differences, she’s always been, my little sister. I could pick on her but if anyone else did, all bets are off and there’s going to be some furniture moving as the old G’s say. Kim is the exact same with me, she can complain about me but if anyone else mentions me in a bad way-watch out.

Our age difference was the spark to most of our fights and sometimes it still is. I like to tell my sister what to do, from life choices, dating and career advice. Each nugget of wisdom I share with her is always from my personal experience and I want to see her avoid making my mistakes. As much as she and I share similarities in experiences, I’ve realized I have to let her make her own choices.

Which brings me to my mistake.

It’s been hard for me to view her as an adult. Sure, she is a junior in college, has her own apartment, and works two jobs while she’s in school. But to me, she’s still a senior in high school needing my advice on makeup.

When I wasn’t looking, she grew up.

One day she was this loud obnoxious teenager (sorry Kim), and the next she turned into this beautiful woman with a world of possibilities. She stopped needing my advice on makeup and started giving it to others. She stopped dreaming about her place in the world and started carving out her own slice of the pie. My biggest mistake is continuing to treat her like a child when she’s becoming a beautiful woman.

This May she’ll turn 21 years old, and as a gift to her, I intend to break my cycle of treating her like a child. Old habits die hard and I anticipate a long road ahead of me. Even though I fully intend to treat her fairly and as an equal, not a child, that does not mean I’ll stop offering up my unsolicited advice. Offering up advice is rule number one in the big sister handbook.