Such a sad day for sitcom lovers!

The great Katherine Helmond has died at the age of 89.

Her agency confirmed the news on Friday the TV legend passed on February 23 of complications from Alzheimer’s. She is survived by her husband of 57 years (!!!) David Christian.

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Katherine had a long and diverse career on stage and in TV and film but became a legend as matriarch Jessica Tate on the meta ’70s sitcom Soap. She followed with possibly her most famous role, as the fabulous man-hungry Mona on ’80s megahit Who’s The Boss?

On Friday her costars from that show, Alyssa Milano, Tony Danza, Danny Pintauro, and Judith Light shared their love for the fallen star, tweeting:

Katherine Helmond has passed away. My beautiful, kind, funny, gracious, compassionate, rock. You were an instrumental part of my life. You taught me to hold my head above the marsh! You taught me to do anything for a laugh! What an example you were! Rest In Peace, Katherine. pic.twitter.com/HNIH0Ty6MN — Alyssa Milano (@Alyssa_Milano) March 1, 2019

In celebration of Katherine Helmond and her brilliance! https://t.co/vaepWn2bpx — Alyssa Milano (@Alyssa_Milano) March 1, 2019

We all lost a national treasure today. No words can measure my love. pic.twitter.com/eGTf6Ovt3f — Tony Danza (@TonyDanza) March 1, 2019

We lost one of the most genuine and kind people I have ever known. There's not a single person who can say otherwise – she was always smiling, full of heart, and had the best advice. I couldn't have asked for a better grandmother and I will miss her so dearly. pic.twitter.com/0fapCPQWuV — Danny Pintauro (@dannypintauro) March 1, 2019

Katherine Helmond was an inspiration to me and so many others

Her grace, talent and humor will be deeply missed

She is in my heart forever — JudithLight (@JudithLight) March 1, 2019



Judith also shared an official statement, saying:

“Katherine Helmond was a remarkable human being and an extraordinary artist; generous, gracious, charming and profoundly funny. She taught me so much about life and inspired me indelibly by watching her work. Katherine was a gift to our business and to the world, and will be deeply missed.”

And other costars and famous friends and admirers said goodbye as well:

Katherine Helmond was such a class act and incredibly down to earth. She was terrific as my mother on #EveryboyLovesRaymond and I looked up to her as a role model. #RIPKatherineHelmond https://t.co/Yiku05soq4 — Patricia Heaton (@PatriciaHeaton) March 1, 2019

I thought Katherine Helmond was perfection on SOAP. Rest In Peace We lost another good one. — HABFoundation (@ABFalecbaldwin) March 1, 2019

R.I.P. dear Katherine Helmond. You were a joy and an inspiration in my career and my life. — Joe Mantegna (@JoeMantegna) March 1, 2019

RIP Katherine Helmond. What an awesome presence you were in everything you did. A consummate artist ❤️ — Viola Davis (@violadavis) March 1, 2019





[Image via ABC/YouTube.]