Was there a 12 year old boy named Sam Harris on the Titanic?
No. The book written about them is fictional, at least the character of Sam and his dog were fictional. Some of the other characters in the book WERE real people, though, who survived the sinking of the Titanic. The book was written to make it easier for kids to understand what it might have been like to be a young person on board the Titanic when it sank.