Firefly Summer by Maeve Binchy

Kate Ryan and her husband, John, have a rollicking pub in the Irish village of Mountfern . . . four lovely children . . . and such wonderful dreams. But all that is about to change one fateful summer when American millionaire Patrick O'Neill comes to town with his irresistible charm, and money to burn. As love and hate vie for a town's quiet heart, old traditions begin to crumble away. . . . 

Patrick O'Neill builds the grand hotel of his dreams, with its promise of wealth and change. Loyalties are challenged, jealousies ignited, and tragedy strikes before the foundation is laid. Suddenly Kate and John Ryan's lives and family are bound up with the newcomer in ways they can never imagine. And Patrick O'Neill faces his own crisis of conscience and heart as the events he sets in motion take on a life of their own in a town that will never be the same again.