Dimitrios Kambouris/Getty 2022 Guggenheim International Gala, made possible by Dior
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, the Marvelous Mrs. Maisel star 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 winner Ariana DeBose, Tony Award winners Adrienne Warren and Stephanie J. Block and more slept outside, without even a pillow to provide them comfort. One year, a flash-flood warning went off while the stars slept outside; another year, award-winning stage and screen actress Audra McDonald attended 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.
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 show The Big Knife.
"I was making my Broadway debut, and Covenant House was reaching out to a bunch of Broadway shows at the time and asking them to participate," the Emmy winner says. "I was in the earlier days of my career, but I fell in love with this organization and was so moved by one young person in particular that I met during that first Sleep Out event."
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.
Some individuals who are helped by Covenant House might return, even several times. This, Brosnahan notes, is the cycle. And that might bring shame to the individual, but that's where the love comes in.
"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.
She and her Mrs. Maisel castmates 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."