Hank Williams Jr.'s youngest daughter, Katherine "Katie" Williams-Dunning died in a car crash on Saturday night (June 13), leaving a hole in one of country music's most prominent families. On Instagram, her half-sister, musician Holly Williams, shared her grief over the 27-year-old mother of two's death, which occurred while the family was mourning another beloved member.

"I have no words," Williams begins, sharing a final family photo, taken Friday morning (June 12). "I talked the family into taking this picture and had no idea it would be our last together with my precious little sister Katie."

Williams-Dunning is one of two children born to Williams Jr. and his third wife, Mary Jane Thomas. Her brother is singer Sam Williams, and her grandfather is country icon Hank Williams Sr. Her half-siblings are Holly and her sister Hilary Williams, also a musician — both of whom were born to Williams Jr. and his second wife, Becky White — and Shelton Hank Williams, known as Hank III, who is the son of Williams Jr. and his first wife, Gwen Yeargain.

The Williams family was together on Friday following the Thursday (June 11) funeral of Loretta S. Fleming, the sister of Audrey Williams, Hank Williams Sr.'s first wife.

"We all loved [her] dearly," Holly Williams writes, "and now are faced with another one."

"ALL we need is prayers. My daddy. My little brother. Katie's husband ... My niece and nephew. Her Mama. The Dunning family. All of us," she adds. "So. Many. Prayers. Jesus is close. Thank you all."

Williams-Dunning died in a one-car crash on Highway 79 in Henry County, Tenn., about 100 miles west of Nashville. She was driving a 2007 Chevrolet Tahoe, which was towing a boat, when the vehicle crossed a median dividing the highway and rolled over. The Tahoe crossed through the highway's northbound lanes and stopped on the shoulder.

Williams-Dunning's husband, 29-year-old Tyler Dunning, was airlifted to Vanderbilt University Medical Center. Per Holly Williams' Instagram post he is "awake and responding," but the extent of his injuries is not yet clear.

According to her Facebook page, Williams-Dunning was born on Oct. 21, 1992, and lived in Springville, Tenn.. She and Tyler had been married since October of 2015. They have two young children, a 5-year-old son named Beau Weston and a 2-year-old daughter named Audrey Jane.

Williams-Dunning ran a clothing company called Weston Jane, her Instagram page explains, that focused on "moms supporting moms and women supporting women." She enlisted another mother from West Tennessee to print her designs, and sold items made by other moms.

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