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OAK HARBOR, Wash. -- On John Wallace's family farm, family extends beyond his wife and children.

"We have seven mules, and they're like my kids," he says. "They are our four-legged kids."

Wallace's mules are docile, sweet and trusting -- perhaps too much so.

Beginning in January, someone started cutting fences on the farm, creeping onto the property and abusing the animals.

Buster was the first.

"Somebody stood right in front of him with a two-by-four or something and swung it like a baseball bat and hit him right in the eye," says Wallace. "We think they were trying to kill him."

Two weeks later, 19-year-old Lotta was beaten, her leg nearly broken. Her side was slashed with some sort of knife or razor.

"It was obvious this was no accident," says Wallace. "I want to find who it is and humiliate them. I want the whole world to know who could do this to a gentle giant."

And just last week, a third mule named Tucker dropped dead out of the blue.

"He just tipped over and died," says Wallace. "He was healthy. There was no sign of him being sick or anything."

Wallace says his kids are now having nightmares, and he feels like a prisoner.

"I'm stuck in my own home because I have to watch out for these innocent animals. It's a nightmare. It's a living hell."

The family didn't have the thousand dollars for a necropsy, but they did set up cameras around the farm. They captured one picture of what looks to be a person trespassing on their property, but that's all you can see. The infrared image is distorted by what appears to be a headlamp.

A fund entitled "Mule Donations" has been set up at Wells Fargo branches to help pay the family's veterinary expenses. (Account number: 8007561734)

For now, Wallace can only remain vigilant, hoping his mules are left alone.

"They don't deserve this," he said. "They're innocent. They're lovable. They're our family."

Anyone with information about the incidents should call the Island County Sheriff's Office at 360-629-2224.