Stan Love, a former professional basketball player who was the brother of the singer Mike Love of the Beach Boys and a onetime bodyguard and caretaker of the band’s brilliant but troubled leader, Brian Wilson, has died at 76.

His death was announced on Sunday on Instagram by his son Kevin Love, the five-time N.B.A. All-Star who plays for the Miami Heat. He did not say when his father died or specify the cause or location, although he did say that Mr. Love died after a long illness and that his longtime wish was to die at home. He was known to live in Lake Oswego, Ore.

Stan Love, a 6-foot-9 forward who had been a star player for the University of Oregon, was selected ninth overall in the 1971 National Basketball Association draft by the Baltimore Bullets, the predecessors of the Washington Wizards. He averaged 6.6 points and 3.9 rebounds a game with modest playing time over four seasons with the Bullets and the Los Angeles Lakers of the N.B.A. and the San Antonio Spurs, then of the American Basketball Association.

Mr. Love, then with the Los Angeles Lakers, being guarded by Steve Mix of the Philadelphia 76ers in a game in Philadelphia in 1975.Credit…Rusty Kennedy/Associated Press

As his basketball career ended, Mr. Love became Brian Wilson’s caretaker in the 1970s and ’80s, during a turbulent period for Mr. Wilson, his cousin, whose innovative songwriting and flair for sophisticated harmonies were complicated by drug use and mental illness.

Mr. Love said he toured with the Beach Boys for roughly five years. He described that period to The Portland Tribune in 2019 as chaotic.