Billie Eilish said she'd only wear Oscar de la Renta to the Met Gala if the designer ditched fur. The brand said yes.

• Billie Eilish wore a stunning Oscar de La Renta ball gown for her Met Gala debut on Monday.
• But Eilish told the brand she'd only wear the dress if it stopped selling fur.
• She convinced Oscar de la Renta's chief executive to finally change the policy.

What you saw on the Met Gala red carpet was Billie Eilish making her grand debut in a stunning Oscar de la Renta gown made of peach tulle.

But what you might not know is that, behind the scenes, Eilish used her influence to enact a major change in the brand's design policy.

Eilish told the label that she would only wear Oscar de la Renta to fashion's biggest night of the year if the brand stopped selling fur, according to The New York Times.

And after years of holding off on pleas - even from inside the company - the iconic label agreed with the 19-year-old vegan and animal rights activist.

Eilish told the Times' Jessica Testa that she was "honored to have been a catalyst" at the fashion house, adding that she was shocked that "wearing fur isn't completely outlawed at this point in 2021."

Creative directors Fernando Garcia and Laura Kim told the Times that they haven't incorporated fur in their designs for years and told Alex Bolen, Oscar de la Renta's chief executive, that the brand should stop using it entirely.

Bolen allowed them to stop including fur in runway designs, but still had the label selling fur products in stores, even after his mother-in-law (and Oscar de la Renta's widow) Annette told him she thought the practice "was barbaric," according to the Times.

But when Eilish gave the brand an ultimatum, Bolen decided it was time to follow Oscar de la Renta's own advice.

"I thought a lot about what Oscar said - he was a big fan of fur, by the way - that the one thing he really worried about in the fashion business was his eye getting old," Bolen told the publication. "I have to surround myself with people with different points of view."