Alan Thicke's sudden death at just 69 has sent shockwaves across the entire entertainment community.
And RadarOnline.com has learned that no one was more devastated by the iconic actor's death than his celebrity son, "Blurred Lines" singer Robin Thicke, 39.
"Alan passed away in the hospital surrounded by his family, including his son, Robin, and Robin's girlfriend, April Love Geary," a family source said today. "Needless to say, Robin and his family are not handling this well."
But the superstar, whose private battle against alcohol and pills was exposed during a lawsuit deposition in 2014, has vowed to avoid partying in his time of grief.
"Robin has told his close friends that his dad's death is a total wake-up call for him," the insider insisted.
As Radar reported, the beloved Growing Pains star suffered a massive heart attack while playing hockey against his 19-year-old son, Carter, in Los Angeles on Tuesday.
Robin took to Instagram to mourn his father with fans that evening.
"He was the best man I ever knew," he wrote. "The best friend I ever had."
Alan is survived by his wife Tanya and three sons.