Mother's Day (May 9) was an especially sweet holiday for singer RaeLynn this year, as it fell just days after the singer announced that she's expecting her first child with husband Josh Davis.

RaeLynn and Davis shared their news in celebration of the singer's 27th birthday, which also marked 21 weeks into her pregnancy, she says. The baby, a girl, is due to arrive in September. Though the couple had been keeping their news to themselves since January, RaeLynn offered a look into the early weeks of her pregnancy on Sunday, sharing a song that she wrote for her unborn daughter when she was just eight weeks along.

"Wrote this when BB girl was 8 weeks in my belly," the singer says in the caption of the post, alongside a video showing behind-the-scenes footage from her pregnancy announcement photo shoot as well as pictures of her positive pregnancy tests and a sonogram picture. "Happy Mother's Day to all the moms and expecting moms."

The song, which RaeLynn co-wrote with songwriters Drew Kennedy and Ben Stennis, details the intimate first moments when the singer realized she was going to be a mom.

"When I watched those two pink lines arrive that Wednesday afternoon / It went from me just being me to me being me and you," she sings in the clip of the song posted to social media.

"And baby, I just smile thinkin' 'bout your little eyes looking into mine / It's crazy how it's like / Like I already met ya, already held ya / I knew that I loved you before I could tell ya / It was written in the stars / It was tattooed on my heart / You were always meant to be the one / Made for me to love."

When she announced her pregnancy, RaeLynn said that she and Davis had been spending 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.

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