Holly Williams' family is getting just a bit bigger!
The 41-year-old country singer — who is the daughter of Hank Williams Jr. and country legend Hank Williams' granddaughter — revealed that she's expecting her fourth baby with husband Chris Coleman. She shared the announcement with a photo displaying her bump on Instagram.
"I keep forgetting to tell y'all something 😳🥰👼🏼," she teased in the photo's caption.
"Number four will be making a mystery fall debut!!! Thanks to the insanely talented @mandyjohnsonphotography for all that she captures, she's been a friend through many seasons."
Williams went on to share her many feelings surrounding this pregnancy. "I am most curious, awe-inspired, somewhat afraid, and deeply-deeply grateful-for this one, after so many roaring waves threatened to steal the shoreline," she wrote.
"Here's to another wild round @colemantime, and to all the sleep we can possibly get before it is stolen once again, in the most brutal and beautiful manner. Tick-tock…"
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Williams received well wishes from a number of famous friends about the exciting news.
"Here you gooooooo❤️," wrote Gwyneth Paltrow, to which Holly replied, "can't wait for y'all to meet."
"Wow!! So beautiful... thrilled for you , MAMA! ❤️" Reese Witherspoon commented.
Williams and fellow musician Coleman married in Nashville, Tennessee, in 2009. Following the birth of Stella in September 2014, she told PEOPLE that her daughter's name held a special meaning: her first was a nod to a great, great aunt, while her middle — June — was in honor of Williams' maternal grandmother.
"She was the grandparent I was closest to by far and she was just such an amazing, lovely, southern dream of a grandmother to me," said Williams. "It's really important to teach my child about my grandparents and where they came from and why I was so close to them."