Conan O’Brien has said his parents, who sadly died just three days apart from each other this week, raised him with a "strong sense" of the family's Irish roots.

Conan’s father Thomas F. O'Brien, M.D. died on Monday, December 9 at the age of 95, while Conan’s mother Ruth Reardon O’Brien passed on Thursday, December 12 at the age of 92.

Thomas and Ruth had been married for 66 years, and Conan is one of their six children.

In a previous interview with Irish America Magazine, Conan said, "My parents were very proud of their Irish heritage, and they raised us with a strong sense of our Irish roots.

"It's something that's always been a big part of my life."

That "strong sense" of his Irish roots has informed some of Conan's best comedy bits over the years.

Hurrah! I am back in Ireland, 150 years after the British made me leave for doing a crappy talk show in the village.

— Conan O'Brien (@ConanOBrien) October 10, 2012

In 2019, Conan revealed during an appearance on "The Late Show with Stephen Colbert" that, despite being born and bred in the US, a DNA test showed that he is actually "100% Irish."

"This is quite unusual," Conan recalled the doctor telling him, "You are 100% Irish."

"And I thought that was a compliment - that you scored high on a test.

“So I said ‘Thank you very much… do I get a prize? Is this a good thing?'"

"And he said, ‘You idiot, it means you’re inbred!’"

Conan continued light-heartedly: "My people left Ireland, we moved to Massachusetts, we moved to one town in central Massachusetts, and then married each other for about 150 years."

Later, in an August 2023 interview with the Second Captains podcast, O'Brien discussed his upbringing in Brookline, near Boston: "Both of my parents are very Irish Catholic. My mother's side came from the Cork area. My father's family came from Dungarvan [in Co Waterford]. They came to central Massachusetts to take up farming. Irish married Irish.

"I was the first one to deviate. I love to say that I got jungle fever and married a woman who is Irish but also has some Welsh and Scottish. I'm the one who went crazy and dabbled in the dark arts." 

A few months later, Conan even got to chat about his Irish roots with another prominent Irish American, US President Joe Biden.

Conan told the President that his mother worked to instill in him and his family that they are “proper Irish, we are lace curtain Irish.”

He reflected - with a laugh - that despite his mother’s attempts to instill that they were “proper,” he “got into this business where I make a fool of myself.”

Conan has "professionally" ventured to Ireland a number of times. In 1999, he played a clueless American tourist as he wandered the Irish countryside in a (hilarious) segment for his "Late Night with Conan O'Brien."

More recently, Conan visited Ireland for his Emmy-winning show "Conan O'Brien Must Go."

While he found no shortage of craic in Dublin, Galway, and Limerick, Conan also got down to business tracing his family's roots.

Hey, I found my piece of the Auld Sod! pic.twitter.com/1CecGfeqML

— Conan O'Brien (@ConanOBrien) January 11, 2024

Sadly, Conan's parents have passed less than a month after it was announced that he will host the Oscars for the first time ever on March 2.

A joint funeral for Conan's parents Thomas and Ruth will be held on Wednesday, December 18.

Thomas's obituary notes that in lieu of flowers, donations can be made in memory of Dr. Thomas F. O'Brien, Class of 1950, to College of the Holy Cross, P.O. Box DEV, 1 College Street, Worcester, MA 01610, or to The Michael J. Fox Foundation for Parkinson's Research, P.O. Box 5014, Hagerstown, MD 21741.

Ruth's obituary says that in lieu of flowers, donations can be made in memory of Ruth Reardon O’Brien, Class of 1953, to Vassar College, Office of Advancement,161 College Avenue, Box 14, Poughkeepsie, New York 12603.