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Alan Thicke Dead At 69; Entertainment World Reacts On Twitter

2016 has not been a kind year, and now it’s taken one of TV most beloved dads.

Alan Thicke, best known as Dr. Jason Seaver on ABC’s Growing Pains, has died. He was 69.

TMZ first broke the news of Thicke’s passing, which was the result of a heart attack. Thicke was playing hockey with his son, Carter, “when he started having chest pain, then got nauseous and vomited.”

Son/singer Robin Thicke confirmed his father’s death to the L.A. Times and called him “the greatest man I ever met…He was beloved and he had closure. I saw him a few days ago and told him how much I loved and respected him.”

Thicke was also known for composing a number of TV theme songs including Diff'rent Strokes and The Facts of Life.

Considering his sudden death, many of Thicke’s friends in the entertainment industry were beside themselves and took to Twitter to share their grief.

bob saget on Twitter

So sad is the passing of Alan Thicke. Such a good husband, father, brother, and friend. He will be deeply missed. Rest in peace dear Alan.

Dave Coulier on Twitter

RIP Alan Thicke. We skated side by side for years. Say hello to Gordie and The Rocket for me. Our Canadian Mounties sketch @jimmykimmel

Demi Lovato on Twitter

Had the pleasure of meeting Alan Thicke and his amazing wife Tanya a few years back.. my thoughts and prayers are with his family. RIP ????

Alyssa Milano on Twitter

Alan Thicke was always the nicest and happiest person in the room. Gone way too soon. Rest In Peace.

Edmonton Oilers on Twitter

RIP to one of the great ones, Alan Thicke.

Russell Simmons on Twitter

RIP to my brother Alan Thicke. The world has lost an icon. ????????

John Legend on Twitter

RIP Alan Thicke. I grew up watching him and got to know him through Robin. He was always so kind to me. So sad to hear about his passing.

Ellen DeGeneres on Twitter

America loved Alan Thicke. I'm so sad he's gone. Sending so much love to his family.

Lori Loughlin on Twitter

I'm so sad to hear about the passing of Alan Thicke. RIP Alan. ????

NHL on Twitter

The NHL family is sad to learn of the passing of longtime hockey fan Alan Thicke. Our thoughts are with his family and friends.

Ed Helms on Twitter

Rest in peace Alan Thicke - You brought so much light, love and humor to the world! Deeply grateful for your friendship and wisdom.

Chaka Khan on Twitter

Condolences to the family of @Alan_Thicke. If ever there was a time celebs are thinking about our mortality, 2016 is it.

Caroline Rhea on Twitter

I loved #AlanThicke He was a great Canadian and friend. Funny and kind. My condolences to his family. #RIPAlanThicke

Candace Cameron Bure on Twitter

I'm sad beyond words that Alan Thicke has passed away. I've known you since I was 8 years old... https://t.co/GLXSTK1nd7

Ryan Seacrest on Twitter

sad to learn of Alan Thicke's passing. he was a great friend over the years. thoughts & prayers to his family.

Montel Williams on Twitter

Now Alan Thicke... Can we get a do-over on 2016? Too many good people lost and way too many bad people getting lucky... RIP Dr. Seaver ????????

Andrea Barber on Twitter

There are no words for how sad this is. What an honor to have been able to work with him. Rest In Peace, Alan. ❤️???? https://t.co/gVaDcpLRqO

Mindy Cohn on Twitter

RIP to the man who wrote #thefactsoflife theme song, my co-host of the radio show TalkZone & a true gentleman of our business #AlanThicke

Funny Or Die on Twitter

Thanks for the laughs, Alan Thicke! You'll be missed.

Joel McHale on Twitter

@Alan_Thicke was always so gracious & kind to me. A very very cool guy. Rest In Peace my friend. God bless this great Canadian!

CedricTheEntertainer on Twitter

Rest In Peace. To my friend #AlanThicke. This guy was the best. Always a gentleman, funny and... https://t.co/Knj3XrfyFg

Ben Stiller on Twitter

Just heard of #AlanThicke's passing. 1st job in LA was as an intern for him... He was a very nice boss. Sending good thoughts to his family.

David Boreanaz on Twitter

So saddened to hear about the death of Alan Thicke. All heart,loved life and was a true gentleman and hockey brother. R.I.P.

Los Angeles Dodgers on Twitter

The Dodgers offer their sincere condolences to the family and friends of Alan Thicke over his passing today.