The Ghost in the Vineyard - Crystal Cove Cozy Ghost Mysteries, #4

Before his death, Matthew O'Brian had a love of vineyards. His family owned a vineyard in Napa Valley, now run by Matt's sister Susan. So it was no surprise that Matt had helped his good friend Fred Ricci to purchase and establish a successful vineyard. Now Fred is calling again, asking for Matt's help. Unfortunately, Matt is no longer alive, so Sally has to decide if she can help Fred. "What do you need, Fred?" "I need you to find my son.
He's missing, and I suspect the worst." Indeed, the worst did happen. Sally found Fred's son, Tony Ricci, dead in the vineyard, murdered. She is about to call the police when Tony's ghost begs her to find out who killed him. "You have to help him, Sally, " urged Matt. "For us, this is personal." Sally nodded, knowing that she would run into opposition not only from Police Chief Harvey Morris, but also from her daughter, Jennifer.
But how could Sally ignore Tony's pleas for help? Wasn't the reason Sally herself had come back from the dead to help other lost and confused souls find peace?