Martha Stewart's younger sister, Laura Plimpton, died yesterday at her home in Weston, Connecticut, having suffered an apparent brain aneurysm.
Her famous sibling shared a tribute on her official website.
"My youngest sister, and the youngest of the six Kostyra siblings, Laura Kostyra Plimpton, passed away today in Norwalk Hospital," Stewart, 73, posted.
Although Plimpton was rushed to the hospital after falling ill, doctors could not save her, Stewart's message said, going into further detail as follows:
"She woke up Monday morning at 5:30 a.m., did her elliptical and treadmill, then showered and felt ill enough to call her husband, Randy, for help."
"Laura left a living will so she was kept on life support until today so her three children could say their goodbyes, and the testing could be completed for organ donation."
Following her first husband's death, Plimpton went to work for her sister. More than 25 years later, she still ran daily operations at Martha Stewart Living Omnimedia.
"We are so sad, but also happy that Laura had the foresight to donate so many healthy organs to needy people," Stewart writes. "Laura deserves the very best."
"She was an extraordinary employee, mother, wife and sister."
In a 2004 interview with Larry King, Laura Plimpton described the "special relationship" she had with Martha Stewart, who was 14 years her senior.
"I was 5 when she got married ... all I wanted to do was be around her, her husband, and then when Alexis was born, I just wanted to take care of Alexis," Plimpton said.
"She was a mother figure in many ways, a teacher, an employer."