"They miss being at the center of the action," a source close to the Trump family tells PEOPLE about the president's eldest sons

Son-in-Law Jared Kushner’s Position at Center of Trump’s New World Doesn't Sit Well with Don Jr. and Eric

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One of the biggest power players in the First Family doesn’t share the Trump name – and that doesn’t always sit right with those who do.

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Post-election, President Trump’s two oldest sons – Don Jr. and Eric – are known to chafe at the shift in attention to brother-in-law Jared Kushner, a senior advisor to the president with an office in the West Wing, sources tell PEOPLE in this week’s cover story.

“All the attention to Jared is a bit of a sore point and they feel left out of the fun in D.C.,” a source close to the family says of Eric, 33, and Don Jr., 39. “They miss being at the center of the action.”

Kushner – who is the husband of First Daughter Ivanka Trump – resigned as chief executive of Kushner Companies and as publisher of the Observer newspaper in January to take on the role of go-to presidential confidant. Since then, he’s been given one of the biggest portfolios in the White House – tackling everything from criminal justice reform to Middle East peace.

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“Don worked on the campaign and Jared gets the big Forbes cover and they make him out to be a big genius,” says the family source, “and Don is like, ‘No, I worked on the campaign too!'” (Beneath Kushner’s grinning portrait, the headline on that December 2016 Forbes cover read: “This Guy Got Trump Elected.”)

Now, the 36-year-old Kushner has the president’s ear while the Trump brothers, who commanded their share of the spotlight on the 2016 campaign trail, have returned to N.Y.C. to run the Trump Organization in their father’s stead.

“During the campaign, the brothers thrived on being the spokespeople and speaking at rallies and being very visible,” the family source tells PEOPLE. “Jared was able to build much more influence and power by doing exactly the opposite.”

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But, “it’s not like outward hostility [toward their brother-in-law],” the source says.

Another insider tells PEOPLE that Kushner is actually quite amiable: “Jared is hard to crack at first, seems uptight. But he’s hilarious.”

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Kushner, 36, is also entangled in the scandal surrounding the June 2016 meeting at Trump Tower that Don Jr. arranged with Russian nationals promising dirt on Hillary Clinton.

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Emails released by Don Jr. himself earlier this month showed he was eager (“I love it”) to meet with a “Russian government attorney” bringing “high level and sensitive information … part of Russia and its government’s support for Mr. Trump” in his campaign against Clinton.

Kushner and then-Trump campaign chairman Paul Manafort were both copied on the email chain and subsequently attended the meeting.

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With the controversy and legal jeopardy now unspooling from those revelations, the family insider says that, no matter how much Don Jr. and Eric missed the action at their father’s side, “They were better off where they were, they bore no responsibility.”