I know what both sides have with respect to our remaining two parents (my mother, DH's father), and if we were to get anything from either side, it wouldn't be more than maybe 100-300K...depending on how long both live and how much they burn through what they have left. On my side, any inheritance is to be spit between my two sisters and me, on the other side, DH and I would get 2/3 and our sister in-law 1/3. But...not counting on it.
For our estate, yes, we have detailed wills and the estate would be split evenly between my two sisters and the sister in law on my husband's side (his brother's former wife who is like his sister). Each would get 1/3 of our estate (minus some funds for our dogs) which isn't small potatoes as we're nearing retirement. We have no children, but we do have three dogs we love very much. We have instructions on where the two schnauzers go....to their breeder, who has promised that she'd keep the older one who is diabetic and find a good home for our youngest schnauzer. She runs our states schnauzer rescue organization, so she'd go to a good home. Our Airedale is older, and my next-door neighbor loves her and has promised to take her. We set aside 25K for the oldest dog, and 50K for each of the other two (to go to the new owners)....the older two have medical conditions and we wouldn't want their vet bills/medicines to be a burden. Pets are expensive to own.
We've been clear that we want the home and contents to be sold....we don't want any games as far as one party trying to keep the house as a rental or something and fooling with "market value"...etc. I love my one sister's husband....but he's an attorney who is very into real estate, and so I could see a scenario where that could come into play as we live in the same town. Everything is to be sold... and split it up three ways....and the same with our investments...etc.
My older sister would be the executrix of our estate and knows where all of our documents/passwords...etc are. Both of my sisters know what our net worth is as we speak openly about money and investments....and we're all essentially at the same level so it's not a taboo topic. Both sides know we'd like for them to make sure our remaining parents have any resources they may need from our estate, but one is almost 80 and the other is 91, and so we will leave our money to the next generation....our generation to use as they see fit for their families.
It gives me peace of mind knowing all of this is taken care of as we're traveling more and you just never know.