1. Since day one, you've been each other's best friend...
2. ... And greatest nemesis.
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HIS "BUT HOLE" MOMMY!
3. Occasionally, you two joined forces and were each other's partner in crime and brought the worst out in each other.
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But you were quick to put the blame on each other.
4. Your whole childhood was a constant power struggle of getting the most attention.
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Can you just let me enjoy my damn PRESCHOOL GRADUATION?!
5. And you were always trying to outwit, outlast, and outplay each other to earn the title of "Last Sibling Standing."
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MWHAHAHA.
6. If you were the brother, you gave in to at least one makeover from your sister.
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SO PRETTY.
7. And if you were the sister, you probably fell victim to your brother's pranks one too many times.
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Never sleeping again.
8. Old photo albums are filled with pictures basically summing up your love/hate relationship as children.
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GIVE ME THE CAKE AND NO ONE GETS HURT.
9. And no matter how much has passed since then, not much has changed.
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Same old same old tbh.
10. As you've grown up, you've become closer as your sibling rivalry has decreased.
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Just a little.
11. But that doesn't mean you aren't waiting for the opportune moment to unleash blackmail.
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Remember this picture from middle school, HUH KATIE???
12. You can't think of another person in the world who you'd act in the same manner around.
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#SiblingText
13. You're extremely protective of each other when it comes to dating.
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You get her home safe, ALRIGHT?!
14. And more often than not, people think you two ARE a couple when you're out together.
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OMG EW HE'S MY BROTHER.
15. Even though your sibling can still be a little shit from time to time...
Christian Zamora / BuzzFeed