Whats the real thing? Thomas edison got scarlet fever and lost part of his hearing or this other thing?(below)?

The story goes that when Edison, as a young boy, was working as a ‘Candy Butcher’ on the Grand Trunk Western Railroad, he was late for the train’s departure. A conductor supposedly grabbed Edison and boxed his ears, thus causing Edison’s hearing problem the remainder of his life. This was portrayed in the movie "Young Tom Edison.” It never happened. Hollywood, as it often does, especially with historical dramas, takes liberties by embellishing them with lies and half-truths. Actually, his hearing problem was hereditary. His father, as well as other of Edison’s close relatives, had hearing problems. It just ran in the family, nothing more, nothing less.