Not that big of a family, just the four kids and our immediate families, two kids each for 3 of us. It's my dad's 90th birthday, though, so we're all gathering. Mom and Dad live in a very small house, so the rest of us need to stay in a hotel.
It's all being pretty casual. I don't think anything specific is planned for the days, although I might take my lot to the local zoo one of the days. My kids are fond of my sister's kids, but I don't think they've ever met my brother's kids. We none of us live in the same state, and my family is the furthest away, not even being on the same side of the Mississippi river (everyone else has moved west; I stayed in Michigan.)