Well written, this somewhat 'cosy' ghost story, is filled with believable characters, all of which I felt some degree of sympathy for, even the bad guy.
The most disturbing event occurs in the first few pages, seen through the eyes of a twelve year old boy, and would probably be ok for a mature child of that age to read as only the aftermath of violence is witnessed.
It was interesting to see how a brother and sister dealt with the murder of their mother in different ways. One focusing on it almost constantly, the other trying to shut it out but suffering equally due to being unable to commit to a relationship for fear of losing a loved one again.
The romances that eventually arise for the brother and sister provide a new step for both of them, after years of emotional isolation. For me, the ghostly aspect was comforting, the murdered mother watching over her children, rather than any sense of fear. As the revenge aspect was part of the title, I expected/hoped for significantly more suspense as the bad guy neared his end, but this almost seemed a relief for the murderer, and was accomplished without significant drama. His suffering seemed to come from hiding out, drinking and womanising for the intervening twenty years.
Apart from the very occasional f bomb, perhaps two or three in the whole book, a single mildly graphic sex scene, and a fairly sanitised scene of domestic violence, all other 'adult' material is of the fade to black variety which makes this book suitable for a wide audience. I was hoping for a little 'more' but that is my personal preference, and not a reflection on the clear skill of the author to craft a story.