Estelle Harris, who famously played George Costanza’s mother on the ’90s sitcom Seinfeld, has passed away. She was 93 years old.

The actress died of natural causes in Palm Desert, Calif. on Saturday, April 2, Deadline reported, adding that her son, Glen Harris, held her as she passed away. “It is with the greatest remorse and sadness to announce that Estelle Harris has passed on this evening at 6:25pm,” he told the outlet. “Her kindness, passion, sensitivity, humor, empathy and love were practically unrivaled, and she will be terribly missed by all those who knew her.”

Jason Alexander, who played her son on Seinfeld, paid tribute to Harris on Twitter, writing, “One of my favorite people has passed – my tv mama, Estelle Harris. The joy of playing with her and relishing her glorious laughter was a treat. I adore you, Estelle. Love to your family. Serenity now and always. #RIPEstelleHarris”

Their co-star Julia Louis-Dreyfus, who played Elaine Benes on the show, tweeted, “RIP Estelle Harris. I love you. #serenitynow.”