The entertainment world continues to mourn the loss of Catherine O’Hara, the transformative Canadian-born actor whose career spanned almost five decades of comedic, unique genius. Following her passing a few weeks ago on January 30, 2026, at the age of 71, new details from her death certificate have shed light on the cause of her death.
As reported by NBC News, the document issued this past Monday revealed that, February 9, 2026, O’Hara died from a pulmonary embolism—a sudden blood clot in the lungs. While the embolism was the immediate cause, the certificate also listed rectal cancer as the underlying long-term cause of her passing.
The certificate, signed by her oncologist, revealed that O’Hara had been undergoing treatment for cancer since March 2025. The New York Times notes that despite the private nature of her illness, her representatives initially characterized her passing as following a simple “brief illness.” O’Hara passed away at a hospital in Santa Monica, California, having last been seen by her physician just three days prior to her death. The documents also confirmed that the actress was cremated.
O’Hara was a cornerstone of North American comedy, a journey that began, per The New York Times, as an understudy to Gilda Radner at Toronto’s Second City before rising to fame on the influential sketch series, SCTV. She was globally recognized for her range and unique diversity, from her role as the harried mom Kate McCallister in Home Alone to her work as a muse for directors Tim Burton and Christopher Guest, as detailed by NBC News. In her later years, she experienced massive success as the Schitt’s Creek’s oblivious Moira Rose, a role that earned her a Primetime Emmy in 2020.
The news of her death prompted a wave of emotional tributes from former co-stars across generations, a testament to her impact.. Macaulay Culkin, who played her iconic son Kevin in Home Alone, wrote, “Mama…I thought we had time” on Instagram, according to the BBC. Eugene Levy, her professional partner of over 50 years, expressed profound loss, stating that words were inadequate to express his grief. Beyond her classic roles, the BBC also highlights her recent work on The Studio and The Last of Us; her co-star in the latter, Pedro Pascal, noted that there is now “less light” in the world without her. Seth Rogen, a fellow Canadian actor, characterized O’Hara as intuitive and generous.
In addition to her husband, Bo Welch, she is survived by the couple’s two sons, Matthew and Luke. Whether she was shrieking for her son in an airport or surviving the bizarre social ladders of Schitt’s Creek, O’Hara had a gift for finding the most profound human truth, often found in our most “insecure delusions,” according to The Times. While her illness took her from the stage, the decades of laughter she provided will remain for generations to come.
