Rob Goldstone. Rob Goldstone/Facebook Rob Goldstone, the music publicist who finds himself at the center of the latest controversy involving Russia and President Donald Trump's campaign, holds little back on his social media channels.

On his Instagram, which is now private, Goldstone has posted photos of himself and the Azerbaijani-Russian pop star Emin Agalarov with Trump. On Facebook, Goldstone usually posts repeatedly throughout the day about his travels and whereabouts.

It was on Facebook that he checked in at Trump Tower on June 9 of last year with the caption "preparing for a meeting."

That June 9 meeting is what brought Goldstone into the limelight. Goldstone told The Washington Post on Sunday that he arranged the meeting between Donald Trump Jr. and Natalia Veselnitskaya, a Kremlin-connected lawyer, at the request of Agalarov.

The New York Times reported Sunday that the meeting, which also was attended by Trump's then-campaign chair Paul Manafort and now-White House senior adviser Jared Kushner, was arranged on the premise that Veselnitskaya would provide damaging information on soon-to-be Democratic presidential nominee Hillary Clinton.

Donald Trump Jr. said in a Monday morning tweet (his third statement on his meeting) that he "had to listen" after the Russian lawyer had made such assurances about her information on Clinton.

"Obviously I'm the first person on a campaign to ever take a meeting to hear info about an opponent," he tweeted. "Went nowhere but had to listen."

Here are the Instagram photos of Agalarov with Trump (Goldstone appears in the second in the far right corner):

Here's Goldstone's June 9, 2016 Facebook post where he "checked in to" Trump Tower:

Rob Goldstone/Facebook

A day earlier, Goldstone posted a Facebook status jokingly criticizing Clinton's anthem singer from an event the night prior during which she claimed the Democratic Party's presidential nomination:

Rob Goldstone/Facebook

On his Instagram, Goldstone posted a photo of himself wearing a shirt with the word "Russia" printed on it shortly after Trump won the presidential election:

Goldstone, who has recently traveled Brazil, Montenegro, and Croatia, appeared to be in Greece at the time the Trump Tower meeting was reported over the weekend:

The music publicist has a fondness for hats. In many of the photos on his Facebook page, the music publicist is sporting unique headwear: