Janelle Brown says she’s overwhelmed by emotion after fans honored her late son, Garrison, by donating to animal shelters in his name … all as a way to highlight his pet cats.

The “Sister Wives” star shared photos of Garrison and his cats on Instagram Tuesday … saying she was brought to tears after learning High Country Humane and Ark Cat Sanctuary in Garrison’s hometown of Flagstaff received several donations in the wake of his passing.

Janelle — who shared Garrison, as well as five other kids, with her ex-husband Kody Brown — made it clear that this was the perfect way to honor Garrison … who she said loved being a cat dad.”

She adds, “The cats he adopted from both agencies were so important to him.”

Remember, Garrison had rescued a nine-year-old cat — which he named Ms. Buttons — just before his death earlier this month. At the time, Garrison shared that the cat was “on the line for euthanasia” before he intervened.

We broke the story … Garrison passed away in an apparent suicide last week. As we noted, cops say his brother Gabriel was the one who discovered Garrison deceased in his home.

Janelle later confirmed the heartbreaking news … issuing a statement on behalf of herself and her ex-husband, Kody. She wrote … “His loss will leave such a big hole in our lives that it takes our breath away.”

Other tributes from the Brown family — who documented their once polygamist life for 18 seasons — soon poured in for Garrison as well.

He was only 25.

RIP

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