GOODYEAR, AZ - Rene Silva rescued 4-year-old Mollie, a disabled Yorkie that used a doggy wheelchair to get around, two years ago.
"We were going to school to be a therapy dog, so we could go to hospitals," Silva said.
Last month, when Mollie didn't return to the house from her yard in the Sarival neighborhood, Silva went out to find her.
"She was in her cart, face down in the dirt," Silva recalled. "I grabbed her, and my son took her cart off, and we ran up to the vet."
Just last week the pathology report came back. The cause of death was rodenticide toxicosis. In other words, rat poisoning. Silva said she's sure it was no accident. She said she doesn't even have rat poison in her house.
"She wasn't sick, she was a little anxious that day, but that's her -- she likes to play," Silva said.
Goodyear police and the Arizona Humane Society are looking into the case.
"I just want to warn all my neighbors, keep your dogs inside and check your lot yard a lot," Silva said.