Lowcountry Boil by Susan M. Boyer
PI Liz Talbot is a modern Southern belle: she blesses hearts and takes names. She carries her Sig 9 in her Kate Spade handbag, and her golden retriever, Rhett, rides shotgun in her hybrid Escape. When her grandmother is murdered, Liz high-tails it back to her South Carolina island home to find the killer. But when her police-chief brother shuts her out of the investigation, she opens her own. Then her long-dead best friend pops in and things really get complicated. As more folks turn up dead, Liz must use more than just her wits and charm to keep her family safe, chase down clues from the hereafter, and catch a psychopath before he catches her.