1. How to win an argument. 

Especially being the older sister, I have found my way to win every argument. Whether its sitting in the front seat or using the shower first, seniority goes a long way.

2. How to know when it's time to end the argument. 

First, keep in mind that this isn't the same as losing. I can proudly say I have never lost an argument to my little sister (all though she might say otherwise.) There comes a point however, when you grow up and realize not all arguments are worth having.

3. How teamwork is always better. 

Getting into arguments with your parents is unfair, they can always just pull the "because I said so" card. However, when you have a sibling on your side, it makes the playing field a lot more even.

4. How nice it is to have someone know you so well. 

From kindergarten fights with friends to high school break ups, my sister has seen it all. She knows exactly when something is upsetting me or I had a rough day, and she knows when to talk to me about it or leave me alone.

5. How to always be on someone else's side, no matter the circumstance. 

I think my sister could do literally anything (accept to me of course) and I would defend her to my grave. No matter how many fights you get in, your sister will always have your back. It's unconditional love between all of the fights and hair pulling.

6. How to be someone's "person". 

Grey's Anatomy reference, but whenever something big happens to me or my sister we call each other first. From stupid things to big things like getting into college, we are the first person we want to tell exciting news to.

7. How to be so immensely proud of another person. 

Granted, there are some days when I want to kick my sister out of the house. But there are also some days when I feel like the luckiest girl in the world to have her as my sister. Seeing her grow up into the impressive women she was has made me so incredibly proud.