The entertainment world was left in disbelief as details surrounding Catherine O’Hara’s passing emerged shortly after the beloved actress’s death.

Famed for her unforgettable performances in “Home Alone” and the hit series “Schitt’s Creek,” O’Hara passed away at the age of 71 on January 30.

A report from the Los Angeles County Medical Examiner’s Office, acquired by TMZ, disclosed that the cause was a blood clot in her lungs.

The official cause was identified as a pulmonary embolism, with rectal cancer noted as a contributing factor.

This revelation marks the first public acknowledgment of O’Hara battling cancer.

Catherine O’Hara’s cause of death has been revealed after she died aged 71 on January 30

According to the Mayo Clinic, a pulmonary embolism occurs when a blood clot, often originating from the leg or pelvis, becomes dislodged and travels to the lungs, a condition associated with deep vein thrombosis (DVT).

Key risk factors include surgery, prolonged immobility, cancer, pregnancy, hormone therapy, and smoking. 

Rectal cancer is a kind of cancer that starts as a growth of cells in the rectum, per the Mayo Clinic. The rectum is the last several inches of the large intestine. It starts at the end of the final segment of the colon and ends at the short, narrow passage known as the anus. 

Earlier in her adult life, she was diagnosed with dextrocardia with situs inversus, a condition where the heart is located on the right side of the chest. 

Soon after O’Hara died, her family said that the star suffered from a ‘brief illness.’

An ambulance was called out to the actress’s home in Brentwood, Los Angeles, just before 5am on the morning of her death and she was reported to be in a ‘serious condition’. 

She passed away in a hospital in the city.

Her husband, Bo Welch, and their sons, Matthew and Luke, shared an obituary, and soon after, there was a private celebration of life.

The last time she was seen in public was at the Angel Awards at the Proper Hotel Santa Monica on October 16 last year. The event is Upward Bound House’s signature gala.

The last photo of O’Hara, seen left with her husband, Bo Welch, at the Angel Awards at the Proper Hotel Santa Monica on October 16 last year. Right, at the Emmys in September

A guest told the Daily Mail the star appeared slender. ‘Her face was almost gaunt, but she still looked very pretty – she is a striking-looking woman – and she had a touch of glam going on. She hid her figure in a bulky green pinstriped suit.

‘She seemed to be in great spirits, however, and was very friendly and upbeat and lovely.’

The movie star was born in Toronto, Canada, and was one of seven children. Her first experience of acting was playing the Virgin Mary in a Nativity play.

O’Hara worked as a waitress at the Second City Theater in Toronto after leaving high school. As a waitress, she came across the likes of Dan Aykroyd and Joe Flaherty.

Speaking to People in 2024, the actress said: ‘I was lucky enough to watch everybody.’

O’Hara eventually joined the company in 1974. However, she later confessed that she felt anxious whenever she was on stage.

She told The New Yorker in 2019: ‘My crutch was, in improvs, when in doubt, play insane. Because you didn’t have to excuse anything that came out of your mouth. It didn’t have to make sense.’

The star eventually landed a role on a TV sketch show called Second City Television, which was broadcast on NBC in the 80s. The actress became famous for her impressions of various well-known celebrities, including Meryl Streep and Brooke Shields.

O’Hara made her film debut in 1980, when she starred alongside the likes of John Candy and Eugene Levy in Double Negative.

In 1988, she starred as Delia Deetz, the stepmother of Winona Ryder’s Lydia, in the hit movie Beetlejuice, which proved to be a huge commercial success.

And in 1990, she played Macaulay Culkin’s on-screen mom in Home Alone.

O’Hara, who reprised her role for 1992’s Home Alone 2: Lost in New York, told People: ‘It’s a perfect movie, isn’t it?’

With Eugene Levy on Schitt’s Creek season five in 2019

With Tim Burton, Jenna Ortega, Michael Keaton and Winona Ryder in 2024’s Beetlejuice 

Her other roles included Best in Show in 2000 and 2003’s A Mighty Wind, as well as the Beetlejuice sequel in 2024.

In 2020, O’Hara won the Emmy for Outstanding Lead Actress in a Comedy Series for her performance in the hit TV sitcom Schitt’s Creek, which was created by Eugene and Daniel Levy.

During her acceptance speech, O’Hara, who also won a Golden Globe and a SAG Award, said: ‘I will forever be grateful to Eugene and Daniel Levy for the opportunity to play a woman of a certain age, my age, who gets to fully be herself.’

O’Hara is survived by her husband, Bo, and their sons, Matthew and Luke.