for Jacob's Landing by Daphne Greer
Coping with the recent death of his father, twelve-year-old Jacob Mosher is sent to spend the summer with his aging, estranged (and strange!) grandparents in rural Newport Landing, Nova Scotia. Reluctantly, he trades the security of his foster mum in "Upper Canada" for a blind grandfather, Frank, who dresses like a sea captain and conducts flag-raising ceremonies, and a quirky grandmother, Pearl, who sometimes forgets her dentures and has Jacob running in circles.
Jacob has two short months to figure out how to deal with his ailing grandfather, the surging Avon River tides, and the family secret that's haunting his newfound grandparents. He didn't expect so much danger and mystery to be lurking in tiny Newport Landing.