Death on Nantucket by Francine Mathews

Merry's getting ready for her wedding but she's still a police officer and has to work when called out.  It started out with a missing person and then the body is found on the roof.  The woman liked to sit up there and look out at the sea.  When they find out she was poisoned, it no longer looks like it was a natural death...

Soho Crime and Edelweiss gave me the opportunity to read this book for review (thank you).  It will be published June 6th.  

The adopted woman was staying with her father.  He's got dementia and is confused easily.  He forgot she even came to visit.  It's the fourth of July weekend, so police activity is up and the whole family has come to visit the famous father.  No one knew her very well.  Why would anyone want to kill her?  And how did they do it?

Everybody had a finger in the pot somewhere.  There's high hopes of inheritance, brothers who don't agree on whether to sell the house or not, and a divorced wife cluttering up the scene, too.  It's almost a case of mutual enemies weaseling around trying to get the greatest share of the goods.  Then the father ends up dead.  They think he fell but they found blood in his closet... 

Before the story ends, another family member ends up dead.  There are two confessions on the death of the father.  Nothing turns out like it was planned and almost everyone carries some guilt.  The father was a liar who made a lot of money out of it and he willed it away.  After all that strife and trouble, nobody won in the family fight.