Dorothy Mengering, who became a beloved guest on her son's Late Show on CBS, died on Tuesday.
Letterman's publicist Tom Keaney confirmed Mengering's death Tuesday for The Associated Press. She was 95.
Mengering made frequent appearances on the show before Thanksgiving and Mother's Day.
From The Hollywood Reporter:
"Seen via satellite from the kitchen of her modest home in Carmel, Ind., Mengering was at her comic best for the feature "Guess Mom's Pies," in which Letterman had to pick which one of his many favorites she had lovingly prepared for the holidays.
"Her first on-camera appearance on the CBS show came during the 1994 Winter Olympics in Lillehammer, Norway, when she offered to bring ice skater Nancy Kerrigan hot chocolate and asked Hillary Clinton if the first lady could get the speed limit adjusted in Connecticut.
"Mengering reprised her role as a Late Show "correspondent" for the next two Winter Games in Nagano, Japan and Salt Lake City, and she taped segments from London for Dave as well."
Her death comes only a day before Letterman's 70th birthday, CBS affiliate WTTV reports.
Stephen Colbert, who succeeded Letterman as host of the Late Show, tweeted out his condolences on Tuesday.
"As long as David was home, I would make him a chocolate chiffon pie for his birthday," Mengering told The Indianapolis Star in 2001, reminiscing about the comedian's childhood. "We just put the candles on top of the pie."
"Before Letterman's Late Show retirement in May 2015, he shared a Mother's Day highlight reel starring Mengering. She was seen baking with Hoosier rock star John Mellencamp and touting the prowess of Old Milwaukee beer."
Dorothy Mengering was 95.