Ghosts of Yesterday — Georgia M. Shewmake

The warnings to go away, the strange sounds, the ghost in the window--all these things frightened Julie Robertson when she visited her grandfather at Devlin House. But they did no send her running for safety. Now that bother her parents were dead, and the old man had invited her for a visit, Julie vowed to make her peace with him after a long estrangement.

Even when Julie learned more and more about the unsolved murder here of her Cousin Melanie--and felt her own life was threatened--she stayed on. She kept telling herself she had one good friend at Devlin House: Ron Simon, her cousin's handsome widowed husband. But could she really trust him?