We're not sure who first introduced Gigi Hadid and Lady Gaga, but we hope that whoever did took the opportunity to introduce them with, "Gaga, Gigi. Gigi, Gaga."

In any even, the pair has had a slightly-under-the-radar bond for years that only seems to have heighted lately. Gaga, ever the discerning fashion connoisseur, has emerged as one of the biggest celebrity fans of Gigi Hadid's latest capsule collection for Tommy Hilfiger. She's been spotted wearing sunglasses and a jacket from the GigixTommy line in recent days. Which makes sense considering Gaga surprised everyone by showing up front row for the runway debut of the collection last month in Southern California.

Sure, the fact that Gaga's new man Christian Carino happens to be one of Hilfiger's closest personal friends might have something to with it, but the Gigi and Gaga friendship (which our better senses are urging us not to christen with portmanteau "Gagi") is definitely real and has been developing for years.

Our best guess is that Gaga first became aware of Hadid in the way that most of the world did: her appearances on her mother Yolanda Hadid's former reality show Real Housewives of Beverly Hills. Gaga, a noted fan, cast the older Hadid (then Foster) and some of her cast mates in her "G.U.Y." video in 2014.

The first publicly recorded evidence of a Gigi and Gaga run-in came during the 2015 Met Gala. Gaga, who normally prefers to post pictures of herself alongside the other celebs she mets, posted a candid shot on the young model, clad in a sparkly Diane von Furstenberg dress, on Instagram with a simple heart emoji.

Gaga, who had attended alongside designer Alexander Wang, happened to be on an Instagram spree that night and later posted a photo of the pair together. Incidentally, it was Hadid's first appearance at the Met Gala.

The pair wouldn't pop-up again together in public until about 10 months later at the The Daily Front Row 'Fashion Los Angeles Awards' on the West Coast, but their the pair were all smiles and greeted each other with hugs.

Lady Gaga (L) and model Gigi Hadid attend The Daily Front Row "Fashion Los Angeles Awards" 2016 at Sunset Tower Hotel on March 20, 2016 in West Hollywood, California. (Photo by Donato Sardella/Getty Images for The Daily Front Row)

Donato Sardella

Of course, both appeared at the most recent Victoria's Secret Fashion Show in Paris; Gigi as model and Gaga as a performer. It was nothing but a mutual lovefest. Gigi's sister Bella was invited into the circle as well, naturally. Yolanda sat front row at the show, and after her performance, Gaga gave her a warm embrace.

Hadid told Entertainment Tonight that Gaga is basically her other big sister in the lead-up to the show.

"Gaga has been a great kind of big sister to me," Hadid said at the time. "And has given me amazing advice, and I think she is such a beautiful person that is just set on spreading love everywhere she goes. I think that she is one of a kind, she is amazing."

There's been some friendly Tweets between the pair as well.

Then of course, Gaga appeared front row (with Carino in tow) for Hadid's latest Hilfiger collection.

Apparently she liked what she saw. As per Teen Vogue, Hadid uploaded a pic of the singer wearing sunglasses from the collection to her Instagram stories over the weekend.

Then, this morning, Gaga 'gammed a photo of herself wearing a jacket from the collection on her way to rehearsals for her Coachella performance. Naturally, Gigi quickly re-grammed it.

"Woke up to this!!!!" Hadid wrote. "Seeing people I love, & who inspire me, wear my clothes is one of the most special and heartwarming feelings in the world.. U IN THIS @TOMMYxGIGI JACKET MADE MY DAY @ladygaga."

The caption was accented with a number of emojis.

So there you have it, Gigi and Gaga: closer friends than we perhaps had all realized.

At press time, there was no comment from Taylor Swift on the situation.

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