Phoebe Gates Celebrates New Fashion Collab with Mom Melinda French Gates and Sister Jennifer

“At this party is everyone from every walk of life,” Phoebe Gates said of the event

Phoebe Gates and her roommate collaborated with fashion designer Stella McCartney on a collection of bags and Phoebe's family was there to celebrate the exciting partnership!

Ahead of the fall launch of Phoebe and Sophia Kianni’s digital fashion platform Phia —  which is described on its website as being “the future of fashion” —  they teamed up with McCartney to design a limited-edition capsule bag collection honoring the Women’s Tennis Association, according to Vogue.

At the launch event, which was held at the Stella McCartney Greene Street store in New York City, the 20-year-old Stanford University student was photographed with mom Melinda French Gates and sister Jennifer Gates both of whom appeared to be rocking handbags from the collection as they posed together.

The handbags were created to honor the WTA and celebrate the 50th anniversary of the US Open, the first Grand Slam tournament to offer equal prize money for women, per Vogue.

Related: Bill Gates and Melinda French Gates' Daughter Phoebe Thanks British 'Vogue' for 'Internship of a Lifetime'

<p>Bre Johnson/ </p>

Bre Johnson/

“At this party is everyone from every walk of life — some of our mentors have come, our friends from school are here,” Phoebe told the outlet of the event's guest list.

Kianni, who is also a climate activist, went on to tell the outlet that the launch with McCartney was the first step to what they hope is successful venture.

“Both of our backgrounds, all of it has been about bringing people from grass-roots activism to philanthropy together,” Kianni said. “That’s very much the same spirit we want to honor as we enter the fashion space. We want to identify everyone who is doing incredible things, learn from them, and see how we can accelerate progress together.”

Last month, the roommates also attended the Shawn Carter Foundation's 20th Anniversary Black Tie Gala together.

Related: Bill Gates Celebrates Daughter Phoebe's 20th Birthday with Sweet Tribute: 'I'm So Proud of You'

The launch of their new business has been a long-time coming.

"We're building out an idea to help make fashion more sustainable. We have so much planned for this year," Phoebe said during an interview with The Information earlier this year, without going into much detail about the project.

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She also opened up about her use of social media, saying that platforms like TikTok have been a great way to "tell my own story."

"People have a lot of preconceptions about me, so TikTok has been a chance for me to tell my own story and also use the attention my family name might bring to spotlight issues that are important to me, like women's health and sustainable fashion," she said.

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