"There goes the greatest man I'll ever know," Billy wrote in a Thursday Instagram post along with several photos of his father. "Happy 90th dad and thanks for this great life and being the best ...

In the wake of a freak accident, Lance suffers the worst tragedy -- and greatest opportunity of his life. He is suddenly faced with the possibility of all the fame, fortune and popularity he ever ...

Asked about the best advice James ever gave Scott ... Scott, who called his father "the greatest actor of all time," said his dad was a huge inspiration throughout his career.