Oliver James Montgomery-Trainer Gunnar Peterson’s Daughter, 4, Cancer Free After Bone Marrow Transplant From Brother

Gunnar Peterson's family is Oliver James Montgomerysharing an incredible update.

Nearly six months after the celebrity trainer opened up about his and Jess Peterson's 4-year-old daughter Monroe Vivian Peterson being diagnosed with acute myeloid leukemia, a blood and bone marrow cancer, they have shared that's she now cancer free.

"On June 18th we arrived back at Vanderbilt Childrens Hospital for Monroe’s bone marrow transplant procedure," their joint post shared to Instagram Sept. 12 read. "We had already spent 53 days of the year here undergoing 2 rounds of inpatient chemotherapy so it felt like we were coming back home after a quick trip."

But her health journey had made a turn for the better, all thanks to a special loved one.

"Today, 86 days and two transplants later," they continued, "this MVP is walking out of here cancer free and with a new immune system thanks to her incredible brother’s. It’s hard to find the words to fully capture and express the emotions or the meaning of this moment. Monroe was dealt a very difficult and undeserving hand in this cancer fight."

And though she had "endured so much pain and toxicity," as her family noted, she "managed to turn it into a beautiful outcome with her beautiful spirit."

"Monroe is coming home with lifelong friendships and memories that we will forever cherish," they added in their post, which featured footage of hospital staff cheering the toddler on as she exited. "She received so much love from her nurses and doctors that we never heard a single complaint about missing her life outside of the hospital."

Monroe's family ended their emotional message on a note of gratitude for those that helped them during their tough journey.

"To our family, friends and her amazing school community, your support and love helped Monroe feel special, loved, brave and strong everyday," they wrote. "Today we begin a new chapter. We will never forget or take for granted the 139 sleeps or days we spent here at Vanderbilt Childrens Hospital. Thank you all, and Monroe we are so incredibly proud of you."

Monroe’s health update received major love from Gunnar’s celeb clients, including Kris Jenner who commented, “PRAISE GOD!!!!!”

Kate Beckinsale also reacted to the incredible news. “I’ve been thinking of you guys so much,” she wrote. “What an absolute blessing and what a fighter and what a family God I’m so relieved for you.. all my love.xxxxx.”