Christina Perri is excited but cautious as she moves through her pregnancy.

• In the new issue of PEOPLE, the "Jar of Hearts" singer, 35, discusses her experience being pregnant after her late daughter Rosie was "born silent" in 2020. The heartbreaking moment came after the singer, who shares 4-year-old daughter Carmella Stanley with husband Paul Costabile, had previously suffered a miscarriage in January 2020.

The singer announced in May that she is expecting another daughter and tells PEOPLE they're approaching her current pregnancy with optimism.

"Paul and I are choosing to believe everything is going to be OK," she says. "And after what I've been through, I will dedicate my life to helping other women. I truly believe that is Rosie's purpose."

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Months after Rosie's death, Perri discovered she has a treatable blood-clotting disorder that may have caused both pregnancy losses. Now, after more than a year of intense therapy, the musician has a new album (A Lighter Shade of Blue) and a new mission: to help other women avoid the anguish she experienced by raising awareness about a blood test that can detect disorders like the one she has.

"I don't care how long it takes; I'll never stop," Perri says. "I hope to turn my tragedy into something beautiful."

Perri consulted with OB-GYN Dr. Mary Kerr about the blood-clotting disorder. She is also petitioning the American College of Obstetricians and Gynecologists, which recommends the test only after two consecutive early pregnancy losses, for change. 

RELATED: Christina Perri Wants to Raise Awareness After Pregnancy Losses to 'Turn My Tragedy into Something Beautiful'

"Christina's drive is that if potentially one out of 10 women had the opportunity to screen for disorders, that would prevent a lot of emotional trauma," says Kerr. 

As she continues to move forward, some days are harder than others.

"I don't know if Paul or I will ever not feel that longing for Rosie," says Perri, who honors Rosie with a tattoo of her name on her chest and a rose tattoo on her hand, as well as a rose tree in the garden. "But she will always be in my heart." 

For more from Christina Perri, pick up the latest issue of PEOPLE, on newsstands everywhere Friday.