Ralph Sorensen

My grandfather, Ralph Sorensen, was born in Oslo Fylke, Norway in 1890. As the story goes, he got into some kid trouble at around 13 years old and left his books by the water and stowed away on a ship. He eventually changed his last name to Rivers and at some point a sea captain told him to write home to let them know he was alive. They may have thought he drowned. My grandfather died around 1961 and he and his wife Mary Almeida Rivers had ten children. Is there any information out there on an potential relatives? It would be nice to pass some information on to the rest of the family. His first name may have been the Norweigan form of the name.