‘A.C.O.D.’ actress Catherine O’Hara grew up funny

The Internet is a treasure trove of Catherine O’Hara’s golden comedic moments, from her uncanny impression of an elderly Katharine Hepburn talking about her “first time” on an episode of the Emmy Award-winning sketch comedy series “SCTV” to the wacky, eccentric characters she’s embodied in Christopher Guest’s comedies, such as a travel agent who has never been on a trip in 1996’s “Waiting for Guffman.”

And then there are a few not-so-golden moments — such as a campy Dristan commercial from the late 1970s that features a very young O’Hara suffering from a bad cold until her older sister gives her a bottle of the sponsor’s congestion-relief tablets.

O’Hara’s blue eyes dance with glee when she’s informed the commercial is on YouTube.

“It’s so sad,” cackled the 59-year-old actress during a recent interview at a chichi Los Angeles hotel for her latest movie, “A.C.O.D.,” which opens Friday.

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“I blew my nose all day long and ended up with a stuffed nose,” said O’Hara, who lives in L.A. with her husband, production designer Bo Welch (“Men in Black,” Thor”), whom she met on the set of Tim Burton’s “Beetlejuice,” and their two sons.

“Why didn’t I just fake it? I remember I had to hold the pills. If I am shooting something and suddenly the camera focuses on one part of my body, all of my energy goes to that part of the body and it shakes, so they had to put my arm in a clamp. Why didn’t they just use another hand?”

In “A.C.O.D.,” which marks the feature directorial debut of co-writer Stu Zicherman, O’Hara plays Melissa, the self-centered mother of Carter (Adam Scott), a seemingly well-adjusted “adult child of divorce.” The engagement of his younger brother (Clark Duke) forces Carter to reunite with Melissa and his equally self-absorbed father (Richard Jenkins), who are still fighting years after their acrimonious split. Things go from bad to worse for Carter when he walks in on his parents having sex and discovers they have rekindled their romance.

“There are people in the world you want to work with, like George Clooney,” said Zicherman, who has been an unabashed O’Hara fan since watching “SCTV” when he was a kid. “I wanted to work with Catherine O’Hara. Lord knows she’s funny, lord knows she’s dynamic, but Catherine is real and you don’t find that in comedians. I feel like so many comedians are operating from a deep place of insecurity. The first time I talked to her on the phone, she was driving her kids in a carpool. I expected her to be kooky and weird, but she is so grounded.”

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“She is a sweet, curious person,” said Scott (“Parks and Recreation”). “Shooting our scenes, I felt like I was really having the conversation with the person rather than just two people acting separately in a scene together.”

Especially in a pivotal sequence in a restaurant where Carter confronts his mother.

“Her character was toying with my character,” Scott said. “It was the way a mother would do it if she was not willing to admit a mistake. She was doing something you would see in life — it was not something that was lifelike.”

Perhaps the secret to O’Hara’s comedic genius is the fact that her parents encouraged her to be funny. Even at the dinner table.

“Everybody in my family is funny,” said O’Hara, who grew up in a large Irish Catholic household — she has six siblings, including singer Mary Margaret O’Hara — in Toronto.

“The way to get attention at the dinner table was to have something funny to say. We would all tell stories of who we saw that day and what happened. We would interrupt each other. It was like we were carrying on 10 conversations at the same time and you are in on all of them. You didn’t want to miss out on any of them.”

susan.king@latimes.com