The SPCA is investigating the death of three cats from the same family in Templeton, all of which died from acute kidney failure.
The cats, Breeze, Murray and Grace, were euthanised just days apart.
Earlier this month, 10-year-old Breeze became unwell suddenly and his owner, who has asked to remain anonymous, took her to the vet.
They told the Herald Breeze was diagnosed with acute kidney failure and was euthanised.
To the owner's horror, when they arrived home they found Breeze's brother, Murray, in the same condition.
"I took him to the vet and they had a look and told me there was nothing wrong with him. They said if his condition deteriorated to bring him back."
Later that night, a third cat, Grace, started to develop the same symptoms.
Five days after Breeze was euthanised, Murray and Grace were both taken to the vet.
"We were advised that Murray was in acute kidney failure and needed to be euthanised.
"Grace also had acute kidney failure and the vet said it was the worst that she had ever seen so she was euthanised too."
They went to the SPCA to raise a welfare concern in regards to the three dead pets.
"It has been an emotional rollercoaster. This has absolutely devastated my daughter and I."
The owner believes the cats have been deliberately poisoned by a neighbour.
The cats' kidneys are currently at the lab being tested, they said.
A spokesperson for the SPCA confirmed they are investigating the deaths but cannot comment any further.
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