Ivana Trump's Advice for Donald as He Turned 75 - and Even Though He 'Hates His Birthday'

Taylor Hill/Getty Images; Mark Wilson/Getty Images From left: Ivana and Donald Trump

As Ivana Trump knows well, ex-husband Donald Trump is no fan of birthdays - so she had some advice for the constantly controversial former president as he turned 75 this week.

"Donald hates his birthdays," Ivana told PEOPLE on Monday. "So I did speak to him and wished him happy birthday and told him, 'Don't worry about your age. Age is just a number, and his and mine [are] unlisted.' " (This, she noted, was something of a joke.)

Ivana's ex-husband, with whom she shares sons Donald Trump Jr. and Eric Trump and daughter Ivanka Trump, kept a low profile on Monday in Bedminster, New Jersey, where he celebrated at his golf club.

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A source told PEOPLE he was expected to play golf while "the family will celebrate Donald's birthday together as they usually do."

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Don Jr., 43, posted an Instagram video of a birthday singalong for his father at Bedminster - where he was joined by Don Jr.'s girlfriend, Kimberly Guilfoyle; football legend Herschel Walker; Republican lawmakers and others - though it wasn't clear which other family members were with him.

"As much as 45 doesn't love birthdays it was great to be there," Don Jr. wrote in his caption.

It was also unclear if former First Lady Melania Trump and the couple's teenage son, Barron, were in Bedminster, where the former president relocated from their Mar-a-Lago Club in Florida for the summer.

(Spokespeople for the family didn't respond to a request for comment.)

Jemal Countess/Getty Ivanka Trump (left) and Ivana Trump in April 2013

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President Trump didn't publicly make note of his birthday Monday but did release several statements to the media - via email, since he was banned from social media after the U.S. Capitol attack.

Sources have said Trump has spent most of his days since leaving the White House golfing and lunching at his clubs, meeting with Republican leaders and a loose coterie of aides to mull his future and continuing to push false claims about his 2020 election loss.

For her part, Ivana has said she is happy for her family to be free of Washington, D.C. - particularly her kids.

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"I just want them to be able to live their normal lives - normal lives," the businesswoman and former model told PEOPLE last year. "Not the Washington life and all that, just in New York or wherever they're going to be and just live their normal lives."

"I think they enjoyed being around Donald and running the election and seeing what will happen, but now it is - thank god - over," Ivana said in November. "I'm not really sure what they are going to be up to."

Of the former president, she said then, that like birthdays "he hates to be a loser, that I'm sure of."

But, she added, "He has plenty of money, places to go and live in and enjoy his life."

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