Mom shares moment of 'pure happiness' when 9-year-old son finishes cancer treatment

A mom captured a moment of "pure happiness" with a video of her 9-year-old son who was overjoyed as he was finally cancer free.

Ashley Cotter posted a video on Facebook of her son Steven, who she said was diagnosed with cancer over three years ago when he was just 6 years old, that has captured hundreds of hearts on social media.

"You have never seen pure happiness till you’ve seen a 9-year-old little boy cry the most happiest tears ever to be cancer free and take his last chemo treatment," Cotter wrote.

Although the video did not have sound, she wrote, "you can just feel it" and called it "one of the most proud moments I've ever lived!"

"It was absolutely horrible to hear the words 'your son has cancer,' absolutely heart wrenching; but to finally be here at the end and to have witnessed my 9-year-old boy beat cancer and do his chemotherapy treatment with a smile on his face and his head held high was absolutely amazing," she told ABC News.

The mother from Oklahoma added that the moment was, "such a blessing my baby was giving a new beginning."

The original video has been viewed on her Facebook page over 14,000 times and counting.

Steven had his first treatment on Aug. 29, 2016, just three days after he was diagnosed with high-risk Acute Lymphoblastic Leukemia.

Over the past three years, Cotter said her son has had multiple blood and platelet transfusions, tried various treatments including spinal and port chemotherapy, and had many hospital stays.

Steven underwent chemotherapy "everyday until last Saturday evening, when he took his last chemo pill!"

"We in all honesty have came so much closer as a family, came closer to God and always kept the faith," Cotter said.

Cotter said her son was seen in the video with his dad, younger brother and his best friend, whose parents have been close family friends for 13 years.