In high school, Clooney was popular and very athletic. He played basketball and at one time aspired to be a major league baseball player, even trying out for the Cincinnati Reds in 1977.
But this jock was also somewhat of a nerd who was president of the high school science club.
After high school, Clooney went to Northern Kentucky University, but dropped out to pursue acting.
"As soon as he finally decided at age 20 or 19, I guess, that film acting is what he wanted to do, then he was just like a dog with a bone. He just stayed with that with absolute clarity from then on. And has never backed off," Nick Clooney said.
Clooney saved up, selling lemonade to earn money to go out to Hollywood. When he finally moved, he crashed on the couch of his aunt, famous singer Rosemary Clooney.
"He was not beneath being her chauffeur when she needed someone to drive the car when she was on tour," said Oscar expert and film historian Tom O'Neill. "He was not beneath sleeping in the closet at a friend's apartment for a year."
Nick Clooney said he pleaded with his son to pursue anything but acting.
"I said to him, 'George, please... there are 50,000 broadcasters making a living right now. There are 3,000 actors making a living. For heaven's sake, not acting. Don't be an actor,'" Nick Clooney recalled. "And the moral of the story is always listen to your father."
At first, the jobs were few and far between. He shot eight TV pilots that failed to make it to air. In 1984 he was cast in his first recurring television role in a CBS sitcom ironically named "ER," which fizzled.
The big screen would be no kinder. Moviegoers avoided 1986's "Combat Academy," 1987's "Return to Horror High," and 1988's "Return of the Killer Tomatoes."
At that point in his career, he told his mother Nina, he could only get roles in movies with "Return" in the title.
Clooney trudged forward and landed another television role as carpenter George Burnett in NBC's sitcom "The Facts of Life" in 1985.
For the all-female cast, Clooney was easy on the eyes. Lisa Whelchel, who played the bubbly, "Daddy's Girl" Blair Warner on the show, recalled how hormones spiked when Clooney joined the ensemble.
"And then suddenly this man, who was just testosterone with a capital T, walks into the room and changes the entire dynamic," she said. "Somehow the estrogen level went even further up and at the same time we all just turned into little girls again."
Jumping from stints on "Facts of Life," to "Roseanne" and "Sisters," Clooney called himself "the best known unknown actor in Hollywood."
"He had regular or recurring roles on a lot of television programs. And he was being well paid and ... he said, 'Pop, I've got the best of all worlds. ..I am the best known unknown actor out here. I don't have to put up with the nonsense. I don't have to be worried about the paparazzi or any of that kind of problem. All I have to worry about is being a working actor, doing my work,'" Nick Clooney said.
Just as he got comfortable being a relative-unknown in a town of big-wigs, Clooney was tapped to play Dr. Doug Ross on a new NBC medical drama "ER." The primetime hospital serial became a smash-hit and made Clooney into a genuine A-list sex symbol.