Donald Trump's Children Dish on Their Dad's 'Trumpisms' and What They Think of His Hair

— -- Four of Donald Trump’s five children, Donald Jr., Ivanka, Eric and Tiffany Trump, talked with Barbara Walters about what they see in the man they all call Dad.

“His humor's really one of his best qualities, and people don't see that,” Eric Trump told Walters in an interview for ABC News' “20/20.” “It doesn't come across on the news, when he's talking about serious issues. But he is an incredibly funny, incredibly practical person.”

Trump’s three eldest from his first marriage -- Donald Jr, 37, Ivanka, 34, and Eric, 31 -- all grew up in the public eye and have successful careers of their own, while helping to manage their father’s company, The Trump Organization. Tiffany, 22, is Trump’s daughter from his second marriage and is currently a student at University of Pennsylvania. Trump’s youngest, his 9-year-old son Barron, with his current wife, Melania Trump, did not attend the interview with Walters because he was at school.

Meet GOP Candidate Donald Trump's Five Children

When asked which of the kids is most like their father, Donald, Jr., said: “It’s actually very scary. We can go to Thanksgiving, right, and we can all-- we’ll sit there and pick at--“

“Answer the same questions, using the exact same words in the same sequence,” Eric chimed in.

“Trumpisms,” Ivanka added. “But in fairness, I think we’re all like him in very different ways.”

They joked those big family holiday meals -- Donald, Jr. has five kids of his own and Ivanka has two children with one on the way -- can get a little rowdy.

“I relish those holiday meals,” Donald, Jr., said. “We can sort of let loose. I mean, it is a show, I mean, in and of itself. I mean it’s funny, and we have a good time, making fun of each other and just having a blast.”

One of their dad’s most talked about quirks, the butt of many jokes on late-night talk shows, is The Donald’s hair, though his kids said they don’t see anything unusual about it.

“It’s funny because it’s the only hair we’ve ever known,” Ivanka said. “But people seem fascinated so... to us, it’s the norm.”

Tiffany, whose mother is Trump’s second wife, Marla Maples, added that her father, “always says, ‘I’m really happy that you got your mom’s hair, not my hair.”

Donald Jr., the eldest Trump, said he doesn’t like to joke about his father’s hair, “because you never know what happens genetically.”

Trump’s children have all supported him in his presidential run, tweeting and Instagramming photos of themselves at the GOP debates or out on the campaign trail. In September, Eric Trump tweeted a photo of his father signing the pledge to not run a third-party candidacy if he were to lose the Republican nomination.

When Donald Trump, a billionaire real estate mogul who had already re-invented himself as a reality TV star, announced in June he would make a run for the White House and would be handing the reins of his company over to his three eldest children, it was his daughter Ivanka who introduced him as a presidential candidate for the first time.

“I don’t know exactly how it was decided, but I was honored to do it,” she said. “I feel like I was standing there sort of representing our family.”

Her siblings agreed she was the one for the job.

“She's a great messenger,” said her older brother, Donald. “She's got such great poise, I think. And also... I think the way Ivanka delivered the message was perfect, and I don't think any of us could have done it better.”

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