He was born John Cooper Jr. in Los Angeles on Sept. 15, 1922. His mother, Mabel, was a piano accompanist who had worked in vaudeville. His father, himself a piano player and a songwriter, was running a small music store in Los Angeles when they met; he walked out on his wife and son before Jackie was 2.
Growing up, Cooper was always told that his father was dead. But years later he discovered that from 1935 to 1948, his mother had been sending John Cooper $100 a week — money that Jackie had earned.
After his father's departure, Cooper's financially strapped mother went on the road in vaudeville for a period and Jackie wound up living with his maternal grandmother.
To supplement the money Mabel sent home from the road, Jackie's grandmother joined other people standing at the gates of the nearby movie studios hoping to get jobs as extras — jobs that paid $2 a day and a box lunch.
After auditioning for Hal Roach, the producer of the "Our Gang" comedies, Cooper was signed to a $50-a-week contract. Between 1929 and 1931, he appeared in 15 "Our Gang" comedies.
After his star-making role in "Skippy" in 1931, Cooper was signed to a contract with MGM, which kept him busy in more than a dozen movies over the next five years.
Like most child stars, Cooper experienced an adolescent career lull. Deemed by Louis B. Mayer to be a rather bland actor as a juvenile, Cooper's contract at MGM ended when he was 14.
His greatest days as a child star were over. But working for various studios over the next six years, he appeared in nearly two dozen films, including with Deanna Durbin in "That Certain Age," as Henry Aldrich in "What a Life" and "Life with Henry," with Henry Fonda in "The Return of Frank James" and as an adolescent facing manhood in "Seventeen."
But Cooper's career was on a downswing when he joined the Navy in World War II. Having become an adept drummer as a teenager, he spent part of the war playing drums in a band formed by former civilian bandleader Claude Thornhill that played remote bases in the South Pacific.
Returning home after the war, Cooper was a virtual Hollywood has-been at 23. The best he could do was land starring roles in several quickie B pictures, including "Kilroy Was Here," a comedy with fellow former child star Jackie Coogan.
"I was frightened," he recalled of his failed Hollywood comeback in a 1956 interview. "I didn't know what to do. I was a man wearing long pants who still was identified as the onetime child star. People expected me to act, and I couldn't."
He decided to move to New York in 1948 and begin all over again in the theater.
A year later, he made his Broadway debut in the drama "Magnolia Alley." The play closed after only a few performances but earned him good reviews and helped establish him as a stage actor.
The same year, he was signed to play Ensign Pulver in the road company of the hit Broadway play "Mr. Roberts," and he reprised the role in the London company.
Returning to Broadway in 1951, Cooper appeared with Janis Paige in "Remains to Be Seen." Over the next few years, he appeared frequently on live TV dramatic anthologies such as "Kraft Theatre," "U.S. Steel Hour" and "Philco Television Playhouse."
By 1954, Cooper also had become a successful amateur race-car driver and had been married and divorced twice: to one-time movie bit player June Horne, with whom he had his son John; and to New York actress Hildy Parks. Shortly after he and Parks were divorced in 1954, Cooper married Barbara Kraus, with whom he had three children, Russell, Julie and Cristina.
In 1955, he returned to Hollywood to star in "The People's Choice," a situation comedy in which he played Socrates "Sock" Miller, a government naturalist and city councilman in love with the mayor's daughter.
The series, which he co-produced and directed, ran for three years on NBC. It is best remembered for its gimmick: Cooper's character had a pet basset hound, Cleo, whose wry observations could be heard by the TV audience.
Cooper followed that with another series, "Hennesey," a comedy-drama in which he played Lt. Chick Hennesey, a young Navy medical officer. The show, on which he served as a producer and the primary director, ran on CBS from 1959 to '62.
In 1961, Cooper, who had done a few Navy recruitment TV spots while doing the show, was commissioned as a lieutenant commander in the U.S. Naval Reserve, and he served for many years.
