Searching for OPPEN ?

My Grandfather who is known to me as Gilbert OPPEN, was born 10 July 1879 in Norway. Family Tradition states, that as a young boy around the age of 12-15, he ran away from home, stowed away on a ship and was discovered by the ships Captain. He had gotten into an argument with his Step-Father. It was said that they crossed the Atlantic, befriended by the Captain, Gilbert jumped ship before the ships docking. Anyone know of a list, or name for such incidents? Other Family Traditions: Studied to be a Lutheran Minister; Had a 1/2 Brother named Karl CHRISTENSON or KNUDTSON. Grandfather Gilbert was a quiet man, not sharing much of his young life. We know little of his life from the time of his birth to the time he met my Grandmother 20th May 1913 Edmonton Alberta Canada. I did find citizenship papers in the United States after they moved here. That document stated he said he was born in Ostvand Norway. Any help, suggestions, would be greatly appreciated. Thank You Rose Lauzier