Leon got another title shot, this one against WBC champ Larry Holmes, on June 12, 1981, at Detroit’s Joe Louis Arena. Holmes entered the fight with a grudge stemming from an earlier incident. AP IMAGES

Holmes punished Leon and dropped him in the third round. Referee Richard Steele stopped the fight shortly after the knockdown. AP IMAGES

Michael leaves the Philadelphia courthouse where he was arraigned on the charge of possessing an unregistered handgun. AP IMAGES

March 18, 1983: Now WBA light heavyweight champion, Michael defeats WBC champ, Dwight Muhammad Qawi, by unanimous decision. Qawi accused Michael’s promoter, Butch Lewis, of paying off referee Larry Hazzard. AP IMAGES

Michael raises the WBA and WBC belts after unifying the title. Butch Lewis (right, in white) looks as happy as his fighter. AP IMAGES

In 1985, Michael beefed up to take on IBF heavyweight champion, Larry Holmes. Holmes (lower right) looks on as Michael tips the scale at an even 200 pounds. AP IMAGES

September 21, 1985: Michael becomes the first light heavyweight champ in history to take the heavyweight title. Never before had two brothers been world heavyweight champions. AP IMAGES

A pith-helmeted Leon (left), sporting new front teeth, gives the latest heavyweight champion a congratulatory hug. AP IMAGES

Michael beats Holmes a second time—in a razor-thin, hotly disputed decision. AP IMAGES

Stripped of his belt for leaving the HBO heavyweight series, Michael took a $4 million payday to fight six-foot-six Gerry Cooney. The only title on the line was Ring magazine’s, which recognized the lineal champ. Michael downed Cooney in the fifth; the fight was stopped later that round. AP IMAGES

Michael shows off his Ring magazine belt after the Cooney fight. He’s flanked by referee Frank Cappuccino (left) and promoter Butch Lewis (right). Lewis is gunning for Tyson. AP IMAGES

Michael trains in Pleasantville, NJ, for his fight against undisputed champ Mike Tyson. The fight, billed “Once and for All,” would gross over $100 million. Michael would earn $13.5 million. AP IMAGES

June 27, 1988: The opening bell for Tyson-Spinks was delayed. Rumor was that Michael was too intimidated to leave his dressing room. The holdup lasted longer than the fight: Michael was knocked out in 91 seconds. AP IMAGES

July 27, 1988: Michael wipes a tear from his eye during his retirement luncheon at New York’s famed Tavern on the Green. AP IMAGES

Leon was rarely present during his sons’ early years, but has been more involved with them as adults. He was often seen rooting on Cory, a former undisputed welterweight champion. AP IMAGES