NEW YORK (AFP) - Who does Donald Trump truly listen to? His adult children have been ever-present throughout his meteoric political rise. But the family clan also extends to his son-in-law, Jared Kushner, who shuns the limelight but whose role appears increasingly pivotal.
When the president-elect visited the White House last week, a few seconds of footage - of the telegenic 35-year-old walking in the gardens beside Barack Obama's chief of staff, Denis McDonough - spoke volumes about the place Ivanka's husband has carved out at Trump's side.
Kushner's only official role is as member - alongside Ivanka, Eric and Donald Jr - of the transition team tasked with building the Republican billionaire's administration between now and his Jan 20 inauguration.
But despite his lack of political experience, the businessman is believed often to have the final word in advising Trump, according to The New York Times, which expects him "to wield great influence over the new president regardless of whether he holds a formal title."
That influence is already playing out at Trump Tower, where the President-elect's team has been taking shape since the end of last week - in a process reportedly fraught with vicious infighting.
When two transition officials were ousted on Tuesday (Nov 15), The New York Times reported that they were victims of a purge orchestrated by Kushner.
Trump transition official Jason Miller dismissed the reports as "palace intrigue" pushed by people bitter at the election outcome.
But several US media similarly reported that Kushner was working to drive out associates of New Jersey Governor Chris Christie, who himself was removed on Friday as head of the transition team.
The feud is personal: back in 2004, then-US attorney Christie prosecuted and jailed Kushner's father for tax evasion, witness tampering and illegal campaign contributions.
His father's fall from grace is said to have left a profound mark on the young Kushner, according to the New Yorker.
Back in July, it was already reported that he flat-out blocked Christie as Trump's running mate.
So is Kushner a modern-day "Rasputin" figure, whispering into the ear of the political novice Trump as he prepares to assume power?
For Jeanne Zaino, professor of political science at Iona College in New York, it is safe to say Kushner prefers the shadows - unlike his wife Ivanka, a successful businesswoman and potent surrogate for her father during the campaign.
"Jared Kushner is much more private," said Zaino. "He almost never speaks publicly, you don't see tweets. You get the sense he is much more comfortable working behind the scenes."
The Harvard graduate, she said, earned Trump's trust though sheer hard work on the election trail where he is believed to have written several of the candidate's speeches. He is also thought to have pushed out his first campaign manager Corey Lewindowski, back in July.
According to a BusinessWeek investigation, Kushner - who 10 years ago acquired The New York Observer lifestyle newspaper and revived its fortunes by taking it online - played a key role in promoting Trump's message on social media.
He reportedly hired a Texan online marketing specialist named Brad Parscale, and built a highly efficient team tasked with mobilising Trump supporters, and discouraging potential backers of the Democrat Hillary Clinton.
In some ways, Kushner's life story is similar to Trump's.
Like Trump, he took over the family real estate business, then based in New Jersey, and shifted its focus to Manhattan high-rises.
Like his father-in-law, he was also born into privilege. Author Daniel Golden, who wrote The Price Of Admissions: How America's Ruling Class Buys Its Way Into Elite Colleges, said Mr Kushner got into Harvard only after his father donated US$2.5 million to the university.
But he won his place in the Trump inner circle through sheer loyalty - all the more remarkable as he comes from a family of staunch Democrats who donated generously to the party.
Take this example from July, when Trump retweeted an image of Clinton set against a six-pointed star said to resemble a Star of David, setting off alarm bells in the Jewish community.
Some of Kushner's friends asked if he - as a devout Orthodox Jew - would break with the campaign.
Quite the opposite: Kushner published an op-ed in which he spoke of his Holocaust survivor family, and defended Trump against any charge of anti-Semitism.
"I actually think he likes politics more than he likes real estate," Trump quipped of his son-in-law after clinching the Republican nomination.
The president-elect has reportedly inquired about a top-secret clearance for Kushner to be able to join daily presidential briefings - reports denied by Trump.
Reports say Mr Kushner is seeking legal advice because there are anti-nepotism rules that prevent close relatives of the president from playing an active role in government. He could, however, get around the rules if he does not take a salary and puts his investment fund, his newspaper and his real estate holdings into a blind trust.
What will Kushner do with his newfound political capital?
Observers believe he could be tempted to use it to muscle into the media landscape: already on friendly terms with Australian media mogul Rupert Murdoch, he was reported before last week's election to be playing with the idea of launching into television.
At the time his father-in-law denied any plans for a "Trump TV" network, but observers are not ruling it out.
"It would be an unprecedented move - something akin to establishing a state television station to serve as a propaganda arm of the executive branch," The Washington Post wrote last week. "But so much about Trump's campaign was unprecedented that perhaps we should not expect anything different from his presidency."