Let's face it, there are some things only a best friend understands.
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You know each other so well that almost everything is an inside joke, and you basically have your own language.
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But there's also a secret code to best friendship.
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Whether it's something a best friend should just know to do, like letting you approve of a picture before it gets posted online...

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Openly appreciating (and answering) one of your weird and random questions...

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Or something a best friend definitely should NOT do, like talk to your ex after you've made it clear that he/she is stupid and dumb and you're totally over them so why are we even having this discussion?
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So tell us, what's an unwritten rule of best friendship?
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