Mary Pat Gleason has died at the age of 70.
The actress was best known for starring in sitcom Mom and the 2004 movie A Cinderella Story as well as appearing in an episode of Friends.
Mary Pat's friend and Watchmen actor Ron Fassler broke the sad news of her death on social media on Wednesday night as he asked fans to raise a glass in her honour.
He wrote: "Mary Pat Gleason, one of the dearest and sweetest people I have ever had the pleasure to know, passed away last night at age seventy.
"She has 174 credits on her IMDB page (with one unreleased film still to come), but she was so much more than a wonderful actress: she was one of a kind.
He continued: "So caring, so funny, and so delicious to be around, that I find it hard to imagine a world without her shining presence and smiling face.
"My heart goes out to all who knew and loved her (all one million of you). Let's all raise a glass to her this evening as one and offer a final toast and a fond farewell in her memory.”
One of Mary's last roles was on CBS show Mom alongside Anna Faris and Allison Janney. She also appeared on Life in Pieces last year.
Friends fans will remember her as cranky Nurse Sizemore in The One With George Stephanopoulos.
Mary's character greeted Ross Gellar at the hospital after he was injured by a hockey puck.
The actress' manager told Variety: "She was a fighter to the end."