'Counting On' grandmother Mary Duggar's cause of death revealed

The Duggar family is mourning a great loss.

A day after the family shared the tragic news that Mary Duggar, the mom to Jim Bob Duggar, died on Sunday, a rep for the Washington County Coroner’s office tells ET that Mary died of drowning, from what appeared to be a slip and fall into a swimming pool.

On Tuesday, the family shared a statement about their beloved grandmother's passing on their website and social media.

"We are so sad to share that Grandma Duggar (Mary) passed away Sunday afternoon, June 9th, 2019," the family wrote. "Mary Lester Duggar grew up in Farmington, Arkansas and was married almost 50 years to J.L. (Jimmy Lee) Duggar who preceded her in death."

"Mary found great joy in sharing her love for Jesus and her own story of how at age 15 she asked Christ to forgive her for her sins," the post continued. "It was at that time she committed the rest of her life to live for Him, a commitment she kept with devotion. She loved to share with others how they too could be forgiven of their sins, live a fulfilling life as a Christian, and one day spend eternity in heaven."

Mary -- who is survived by son Jim Bob, her daughter, Deanna, 21 grandchildren and 13 great-grandchildren -- was a real estate broker who often appeared on 19 Kids & Counting and Counting On.

"She is greatly loved and will be missed so very much! She lived a tremendous life as a follower of Christ, a wife, a devoted mother, a loving mother-in-law, and a much-loved grandmother," the post read. "Proverbs 31:10-31 describes the virtuous woman, indeed she personified these beautiful verses with her life. We deeply appreciate your prayers for our family and all who loved Mary during this time."

Jill Duggar, who's married to Derick Dillard, took to Instagram to share her own tribute. The mom of two posted a pic of her sons -- Israel and Samuel -- with Mary.

"My heart breaks 💔 My grandma died suddenly today! She was an amazing woman of God and such a great example to so many! 🌸," Jill wrote. "Grandma, you are greatly missed by all who knew you! 💕 She was a feisty, incredible woman who always took the time to talk about Jesus with everyone she knew!"

"I know she was ready to check outta here and get her new body in heaven before the old one started giving her too much trouble! 😉" she continued. "We miss you so much!! 😭💔#maryduggar #rip #grandmaduggar #safeinthearmsofjesus❤"

Anna Duggar, who's married to Josh Duggar, also posted about her family's loss alongside photos of Mary with Anna's six children.

"Great-Grandma Duggar went to heaven today to be with Jesus! 😭 What an awesome woman of faith and such a loving example of God’s love," she wrote. "She was a true soul-winner and loved everyone she met, telling them to turn from sin and trust Jesus for salvation! Miss her soooo much and we cherish each moment we were blessed to spend together! Lots of tears being shed here — grateful for all the prayers! 💕😭"

Likewise, Joy Duggar and her husband, Austin Forsyth, posted about Mary on their shared account with family snaps.

"06/09/19 Grandma Duggar... She was a strong woman, role model, godly counselor... and my favorite person to watch The Price is Right show with," they wrote. "She is GREATLY loved & missed!💖 Thank you all for your kind words and prayers for our family! #grandmaduggar #maryduggar #safeinthearmsofJesus"