As Holly Williams continues to mourn the death of her sister Katherine Williams-Dunning, she is sharing her admiration for her sister with fans.

Hank Williams, Jr.'s 27-year-old daughter Katie died in a car accident on June 13, after the SUV she was driving crossed the median of a highway in Henry County, Tenn., and rolled over. She was pronounced dead at the scene from injuries sustained in the accident, while her husband, Tyler Dunning, who was a passenger in the vehicle, was taken to Vanderbilt University Medical Center for his injuries.

In a poignant Instagram post on Thursday (June 25), Holly shared parts of a reflection piece she wrote for her sister's celebration of life service, praising her as a loving mother to her two children, Beau and Audrey, and as "the most thoughtful and intentional" aunt to several nieces and nephews.

"You always exuded such joy, laughter, kindness and positivity no matter the situation. Hope was your friend and love was your anchor," Holly says of her sister. She also expresses gratitude for the time she got to spend with her sister in the days leading up to the accident, and a conversation they shared that centered around the value of motherhood and their desire to have their families spend more time together.

"I was always so in awe of your stamina with the high pressure jobs and schedules of you and Tyler, and the constant grace that you showered on your children, making them a priority in the face of exhaustion and overwhelm," she continues, adding that planning Katie's funeral was "the most harrowing job I've ever been faced with."

"We will not shrivel in our beds, we will grieve appropriately and rise up for everyone still here who needs us so much, as you would want us to ... We will all go on with hope in the face of hopelessness, with faith in the face of tragedy, and with the sweet assurance that you are in heaven with those that went before you."

In addition to her father, husband and children, Katie is survived by brother Sam Williams, half-sisters Holly and Hilary Williams and half-brother Hank Williams III.

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