George Christiansen died unexpectedly on Monday, March 13, at the age of 65.
A spokesperson for his sister confirmed the news on Tuesday, March 21.
“The family requests that you respect their privacy during this time of sorrow,” Marth’s rep, Susan Magrino, said.
George famously dropped by Martha’s show, with the pair making a blueberry pie, using the fruit from his very own backyard in Connecticut.
No cause of death has been confirmed as yet, however the New York Post believe a heart attack have occurred.
Along with his 75-year-old sister, George leaves behind his wife Margaret Christiansen and their two kids, son Kirk and daughter Kristina.
He reflected fondly on growing up with Martha.
“We used to have the greatest evenings with a bunch of hospitable people. Martha would make pies and other things for the occasions,” he mused in the book Being Martha: The Inside Story of Martha Stewart and her Amazing Life.
Martha is one of six, including her three siblings, Eric Scott, Frank Kostyra and Kathryn Evans.
Sadly in August 2014, her sister Laura Kostyra Plimpton passed away at age 59 after suffering from a brain aneurysm.
At the time, Martha penned a tribute on her blog.
“Laura worked for me and the company for more than 25 years.”
“For the past several years Laura edited, researched, and often wrote, captioned, and photographed content for this blog and The Daily Wag.”