How do you all handle this?

So today is my niece's birthday. I dread going to my sisters house because I don't like my brother in laws family side. They are okay, but they are outspoken individuals and his brother doesn't get along with his mom so sometimes it becomes an argument. Then his sister if she has a disagreement with her husband then you can see it all over his face which is annoying because it seems like he is mad at all of us. Then his brothers wife has a brother which her brother has a wife. His wife doesn't say hi to all of us when they come in, which I find rude. Anyways luckily will only be there 2-3 hours max. How do you all handle these uncomfortable situations in a family setting. I'm literally only there for my niece and my sister. My mom is going as well and my dad is going even though they are divorced

How do you all handle this?
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