I think my crazy family may have this all beat.
Nanna is in her 80's and has 7 kids, 2 are adopted (one of which is my mom). Mom has been doing here bills and financials for as long as I was alive. Every week when I was a kid we walked or took a bus to her house so mom could write checks, do the bills, take care of the house. She was the second youngest, youngest was also adopted. The eldest, my CRAZY aunt, has spent years bleeding my Nanna dry because of her alcoholism and overall greed. Stuff from house disappears, huge checks cashed that nobody knew about, all kinds of stuff. She had to sell 2 of her 5 houses because of financial mess the eldest put her in.
So Nanna gets sick for a while, things are looking really bad. She and mom have gone over the will a couple times through the years and it's always been the same. "All of my kids are my kids, adopted or naturally born, split everything equally 7 ways". Was that way for decades and even close to the end they went over it again because there was some specific things she wanted some other people outside of family to have. This is before she got really bad.
Now she is lying in bed and basically unable to communicate. She is dying, everyone is coming to visit, she can't speak, it's the end. Nan dies, it was expected, sad but not tragic, no more pain, etc..
Fast forward to reading of the will.
Everyone knows the deal, it's basically a formality. Lawyer starts reading the will.
Eldest gets like 60% of everything. Then it went down form there. 10% to next, a few 5%, last daughter (the one the eldest always hated) gets nothing.
Will tells EVERYONE except the eldest they were ALL adopted. Nobody but my mom and her younger sister knew, Nan didn't want anyone to know.
Everyone is shocked, they look at the will and the signature is chicken scratched, not really her signature, dated after Nan was already uncommunicative.
Basically crazy aunt had a new will written, according to what she wanted, and then went in and held her hand to sign it. Lawyer was family friend for years and years, but always really sleezy and close with crazy aunt.
Gets even worse.
While the will is being read the house is being emptied by an appraiser. TONS of old antiques and jewelery and who KNOWS what else stuffed in the nooks crannies and mattresses. They get back to house a couple days later and it's cleaned out. Crazy aunt says "don't worry, you'll get your share".
So they start talking about lawyers and the "patriarch" of our family, Nan's very elderly brother tells everyone to leave it alone. Another lawyer says the defense for my aunt will come out of the estate and by the time it's all over so much in fees comes out that it's barely worth it.
Houses all get dumped cheap, everything disappears, everyone ends up with barely anything except the aunt.
She dies less than a year later, her son refuses to admit his mom did anything wrong and although he and my mom were best friends their whole lives they stop speaking.
Entire family doesn't speak to each other, noly after a couple funerals last year, 20 years later, are things finally thawing a little bit.
Unbelievable greed.