Jake Walter Nicklaus was pronounced dead at Palm Beach Gardens Medical Center at about 6:30 p.m., said Palm Beach County sheriff's spokesman Paul Miller.
The son of Steve Nicklaus, the toddler had been playing in the hot tub with his 4-year-old brother and their nanny, Miller said. The three left the pool area and went into the house, but Jake slipped away and went back through a sliding door to the hot tub, Miller said.
The nanny quickly realized he was missing and discovered him in the water, Miller said. She performed CPR until fire-rescue workers arrived. The boy was breathing at the time, he said.
He was brought to the hospital and died about an hour and a half after rescuers were called, Miller said.
According to the preliminary investigation, the death appeared to be accidental and there was no reason to suspect foul play, Miller said. An autopsy was planned to confirm the cause of death.
He said there was a child barrier around the entire pool area.
A winner of 18 majors and five-time winner of the PGA Player of the Year, Nicklaus most recent action was on Feb. 5 when he returned from a long layoff following back surgery to win the Champions Skins Game.
He is due to serve as captain of the U.S. team in the Presidents Cup competition this fall.
Steve has collaborated with his father on several golf course designs.
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