NEW YORK, NEW YORK - NOVEMBER 09: Rachel Brosnahan attends the 2022 Guggenheim International Gala, made possible by Dior at Guggenheim Museum on November 09, 2022 in New York City. (Photo by Dimitrios Kambouris/Getty Images 2022 Guggenheim International Gala, made possible by Dior)

Rachel Brosnahanis celebrating her 10-year anniversary. No, not to her husbandJason Ralph— they married in 2016 — it’s for the other love in her life:Covenant House.

The nonprofit organization provides housing, food and healthcare to some of the 4.2 million children and youth who are currently facing homelessness in 31 cities in our country. The organization also works in five other countries.

On Sunday, theMarvelous Mrs. Maiselstar will hit the streets for Covenant House’s annual New York City Sleep Out, which raises money and awareness for the unhoused. Provided with only a cardboard box and a sleeping bag, participants sleep outdoors, not to simulate homelessness but to spotlight the critical issue.

“I’m honored and thrilled to be participating for the 10th time,” Brosnahan, 32, tells PEOPLE exclusively.

For years, Broadway stars including Oscar winnerAriana DeBose, Tony Award winners Adrienne Warren andStephanie J. Blockand more slept outside, without even a pillow to provide them comfort. One year, aflash-flood warningwent off while the stars slept outside; another year, award-winning stage and screen actressAudra McDonaldattended the event pregnant. But the stars wouldn’t let anything stop them from the cause at hand.

The event is also now available to attend virtually.

Rachel Brosnahan/Instagram

Rachel Brosnahan/Instagram . https://www.instagram.com/p/B-hTAPklRsu/.

It’s Covenant House’s specific mission to youth that grabbed hold of Brosnahan ten years ago. She had just begun work on the Broadway showThe Big Knife.

He was 23 years old, Brosnahan says: “I was also 23 at the time. And we were sitting across from each other at this table. And I was really struck at the idea that, with such a few small shifts in circumstance, we could be sitting on the opposite side of the table.”

So many of the young people who arrive at Covenant House for the first time have never been told that they are loved, Brosnahan says, adding: “They have never been told that there is a bright future ahead of them and given the opportunity to dream. And that’s one of the things that Covenant House provides. They provide their care, and it makes a huge impact on young people, it begins the journey of breaking the cycle of homelessness before they reach adult homelessness, which is a more challenging cycle to break.”

What Brosnahan learned — and therefore expanded her advocacy — is that LGBTQ+ youth are even more at risk.

“LGBTQ+ young people, in particular, are exponentially more likely to experience homelessness than their non-LGBTQ peers. And when you are a young person experiencing some form of housing instability or homelessness, you are at the mercy of so many of the adults around you and don’t necessarily have the same kind of resources or the autonomy of your adult peers,” she says.

“There was a young woman who I met during one of my earliest Sleep Outs. We can call her A, but she was telling me that it was actually the fourth or fifth time that she had returned to Covenant House. And when we met, it was her fourth or fifth day there,” Brosnahan says.

“One of the things that she valued so much about Covenant House was that it was a judgment-free space. She was welcomed back each time with open arms. She went to college after that. I think were it not for that safe space where she was invited back with open arms, more than a few times, she may not be where she is today.”

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And where is Brosnahan today? Well, she’s a big star. But she is leveraging that stardom for the same organization she believed in a decade ago, pre-Emmys and pre-Maisel. Her costars from the show will join her for the Sleep Out, too.

“I am so thrilled that so many of my castmates are coming.Marin Hinkle,Michael Zegen. And we have other amazing folks too: Stephanie J. Block, Audra McDonald…”

She and herMrs. Maiselcastmates participate every year because of the spirit of unconditional love, she says.

“That’s the great gift of unconditional love, because it’s not something that you need to think about because it’s just there,” Brosnahan tells PEOPLE. “Everybody deserves to be loved and supported that way, but you do notice when it’s not there.”

source: people.com