In the weeks that followed the devastating loss of their 3-year-old son, River, in early June 2019, parents Granger Smith and his wife Amber sought to find positive ways to carry on their young son's legacy. The couple raised money by creating a tribute T-shirt in honor of River, ultimately presenting Dell Children's Medical Center -- the Austin, Texas hospital where he was treated -- with a check for over $200,000. Now, Amber Smith has shared another way in which her son's life continues to positively impact the world: through organ donation.

"When three different neuro specialists told us that River had a 0% chance of brain recovery ... after shock and reality set in, I thought, 'How can we bury our sweet baby and not try to help others?" Amber shares in an Instagram post. "His body is perfect, his organs are perfect, we had to do something. There are so many people waiting for an organ to save their lives."

Although the decision to donate River's organs was simple, the process was not, Amber goes on to say. Not only would it take time to ensure a recipient was a viable match, but due to his small size, River's organs would need to be measured physically, not just by X-ray. Still, the Smith family couldn't bear to watch the young boy's body being pumped full of drugs for days, so doctors agreed to operate on him the following morning.

"I spent the night laying in bed with him, crying and talking to him while they kept running tests and taking blood. The next morning, family and staff lined the hall for the 'walk of honor,'" Amber goes on to say in her post. "We told them River liked to go fast, so to honor him, they pushed him down the hall faster than they had ever pushed anyone. Granger and I held each other and cried."

The couple had been told they wouldn't know right away which of River's organs had been used. Now, weeks later, the Smiths say that the organ donation gave life to two adults: a 49-year-old woman and a 53-year-old man.

"I cried when we opened [the letter]. Cried out of sadness & cried out of love," Amber writes. "I'm so proud of be River's mama and I'm so grateful to God that he gave him to us for those incredible three years. I pray those two recipients live healthy, joy-filled, full-throttle lives just like Riv."

River Smith died in a drowning accident after accidentally getting into the family's pool, despite the fact that the three-year-old was a strong swimmer and his parents took every precaution regarding water safety. The River Smith tribute shirts are currently sold out, though a new version of the shirt is expected to go on sale at some point in the fall. In the meantime, those who wish to support River's legacy can make donations to directly to Dell Children's.

WATCH: Granger Smith Honors River With "Heaven Bound Balloons"

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