A 9-year-old Oklahoma boy’s emotional reaction to taking his last chemotherapy pill after three years of treatment has gone viral after his mom shared the clip on Facebook. Steven Cotter Jr. was diagnosed with acute lymphoblastic leukemia (ALL) at age 6 in August 2016, Fox 35 reported.

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On Dec. 14, Cotter’s mother, Ashley, caught a video of him breaking down at the family’s living room table while surrounded by the empty containers symbolizing the years’ worth of medicine he had taken, with just one pill remaining. The younger Cotter, who was sobbing at the table, told his mom that his tears were those of joy.

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“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!!” Ashley Cotter wrote, after posting the video. “My baby took his last chemo crying with a smile on his face!!!! God blessed my family! Both my sons have a story to tell!!! Listen and you all will hear of them going further than the stars!!! This is one of the most proud moments I’ve ever lived!!”

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Although the video has no sound, Ashley Cotter said you can “feel” her son’s emotions through the footage. The original clip has been viewed over 19,000 times.