"I am grateful so many fans had the chance to watch Archie grow up," she wrote. "Everyone that got to know him could see his gentle heart and sweet soul. He was loved so much and felt all of it, even winning his Best Appearance award at Bravocon."

Shannon also detailed how Archie was able to spend his last day "doing his favorite things- standing in the ocean, sitting in the park, and eating, a lot of eating."

The reality star—who adopted another golden retriever named Troy last year—continued to say that "the most selfless and thoughtful things Archie did was to bring Troy into our lives so we aren’t alone."

"I keep thinking he is just taking a nap," she added, "but Archie is now a very special angel in heaven and is swimming, running, and playing catch with no more pain. The girls and I are so blessed to have spent 10 years with the most incredible companion anyone could ask for."

As Shannon’s friends and fans expressed their sadness over her loss, her her longtime costar and former best friend Tamra Judge was among those who sent love in the comments.

"Sweet Archie is now running free in Heaven with all the tennis balls his heart desires," she said. "Thinking of you and the girls."

Shannon had previously shared Archie's diagnosis after he'd suffered from several seizures.

"After experiencing multiple seizures, Archie has been diagnosed with brain cancer," she wrote on Instagram May 5. "Our heart aches for our sweet Archie. He means the world to the girls and I. We are going to do everything we can to help him fight this."