My little sister, Alexandra, is two years younger than me, and we've been partners in crime since she was born. Growing up, she was, and still is, my best friend who has taught me more life lessons than I'd like to admit. Despite the ridiculous fights over when we turn out the light to go to bed, what fast food we want for dinner, or whether or not one of us split a cookie in disproportional halves on purpose to have the bigger piece, she's taught me lessons I'll take with me for the rest of the life.

1. I'm not always right.

I have a really bad "I'm always right" attitude... stemming from me being right about almost everything. But, there are times where I'm clearly wrong. Of course, her being the younger sister, she is the very first one to call me out on my falsehood. As angry as I get, she's usually right in these circumstances. She's taught me to really think about what I'm saying and ask myself if it makes sense. I admit my mistakes more often, and I can always count on her to be the first "I told you so."

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2. I can always count on her to give me honest opinions.

Whether it's about an ugly sweater I want to buy or opinions on a boy I want to pursue a relationship with, she is my one and only true and honest opinion-giver. I may not always agree with her, but I know she means well by them, and she's only trying to help me.

3. My secrets are safe with her.

We take secrets to heart, so when I tell her, "please don't say anyting to anyone," I trust that it doesn't leave her head. Of course, if it's something life-threatening, I'd never expect her to keep that to herself, and if she did tell anyone, it's in my best interest, and vice versa. But, I know I can trust her with the deep, the dark, and the downright wrong.

4. It's OK to talk about my emotions and let out a good cry.

I've always tried to be hard as a rock when it comes to my emotions. I'm not one to tell people if something is bothering me, and I'm really not one to let anyone see me cry. By now, she knows when I'm angry, hurt, sad, or having an extremely bad day. The number of times she's come home with pastries for me from work without me saying anything is absolutely incredible. "Ica, it's OK to let it out if you need to" is what she always tells me, and she's always my first shoulder to cry on.

5. She'll always be there for me.

Even in times of utter loneliness and despair, my sister is the one person who has never left my side. She's my shoulder to cry on, singing partner in the car, concert buddy, social justice comrade, and number one fan. I used to think I did all the teaching in this sisterhood, but honestly, she's a wiser 17-year-old than I was. She'll be my maid of honor, the first person I tell when I expect a child and the person I can count on to celebrate all our future accomplishments with.

Alex, my ride or die, partner in crime since '99, I love you always.