On her 27th birthday (May 4), RaeLynn shared some big news: The country singer is pregnant and expecting her first child with husband Josh Davis.

"HAPPY BIRTHDAY TO ME! I’m 27 years old and 21 weeks into carrying our BABY GIRL," RaeLynn shared on Instagram on Tuesday. She adds in another posted that she's "excited for our world to be turned upside down in September."

RaeLynn revealed her pregnancy to People first. The couple have known since January, but waited until RaeLynn's birthday to go public about it because, RaeLynn tells the magazine, "Every year is special in its own way, but what's going to make my 27th year so special on this earth is that I get to be a momma to a beautiful baby girl ... It's the best birthday present!"

Some famous friends, however, already know the news. RaeLynn says Katelyn Brown, Kane Brown's wife, was the first friend she told, "and she cried with me because it's been a dream of mine for a while to be a mama."

"She has been such a light for me during this process," RaeLynn adds of Brown, who is the mother of one-year-old Kingsley Rose Brown. "She and Summer Pardi [wife of Jon Pardi] have become some of my rocks during this quarantine year."

Maren Morris, too -- herself the mom of one-year-old Hayes Andrew Hurd with husband Ryan Hurd -- "was so excited" for RaeLynn and Davis, RaeLynn says. She adds, "I honestly have been so fortunate to have had so many amazing women — Lauren Lane, Brittany Aldean, Hayley Hubbard — help me with tips on what I'll really need. I'm a pretty lucky girl."

RaeLynn and Davis, she says, have spent the COVID-19 pandemic "[thinking] more about the important things in life — and for us, that is growing our family." RaeLynn has Type 1 diabetes and admits that she was worried about managing it while pregnant, but she has "an amazing care team" and shares, "My diabetes and A1C has never been better than it is now."

The couple have their baby girl's name already picked out -- "We agreed on it pretty quickly because it was just too perfect not to," RaeLynn says -- but are keeping it a surprise until she's born. They hope to raise her with a strong sense of faith, self-worth and confidence.

"We of course are no experts, but for us our faith has been so important in our marriage and upbringing," RaeLynn says. "Social media is a scary place, and I just want her to always be confident in who she is and not compare herself."

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