Himself by Jess Kidd

[King Bob]

Mahony is a young man in Dublin, who grew up in the orphanage. He gets a letter that tells him his mother's name and the town she's from, in County Mayo. He goes there to find out what happened to her. In the house where he gets a room, he meets an old woman who was a theater actress, and puts on an annual play. She decides to help him. When he gets there, something happens to him that hasn't happened for years: he starts seeing ghosts. And sometimes they talk to him. There are other supernatural happenings as well. Town secrets are revealed, and they find the truth in the end.
It was a bit leisurely, but picked up speed towards the end. Characters were pretty well drawn I thought. The writing was good. Possibly the mystery aspect would be weak to Greg, although he might enjoy the Irish setting. (The author is from Mayo.) The Yeti might enjoy the magical realist bits.