My side of the family has a blast when we get together. I'm the youngest of 8 and we are spread around the country. It's loud, but it's loud with laughter and not arguments. My wife comes from a very small family (3 kids and one cousin...that's it) and she still gets overwhelmed being around my family when we're all together.
But since this is a bash thread, my SIL can be really tough to take at times. She is always late, never offers to help clean up, and has judgment laced in a lot of her conversations.
A couple years ago, her and her husband showed up at 4pm for a 1pm Thanksgiving meal. My wife was already extremely pissed off since it was only us, her brother's family then her sister's family for the meal, and her sister hadn't called about being late or responded to phone calls.
When my SIL finally stepped in our house (they brought nothing), she says hello, looks around, and then goes "Wow, it looks messier in here than normal."
Seriously.
My wife absolutely lost her ****. She started yelling at them before eventually telling them to leave. It took about 6 months before they started talking and nearly two years before they got together for the holidays....not at our house. My wife can hold a grudge like no other. She swears she will never have them over for another holiday meal.