A family suspected a caregiver was abusing an Alzheimer's patient. So they installed a camera.

Brenda Floyd. Photo / Houston Police Department

Brenda Floyd was turning out lights, getting her 94-year-old patient ready for bed, when she noticed the plate of food on the floor. As the dog scurried away, Floyd turned her wrath on the older woman with Alzheimer's who she was paid to care for.

"I told you to stop feeding that dog human food!" she yelled, punctuating every sentence with a hit to Dorothy Bratten's head, according to a video of the interaction shared by Houston Crime Stoppers.

"Do you have another $4,000 to put that dog back in the hospital? Why do you keep feeding that dog human food, huh? Why do you?

"Get that s- up from there. Get your a- up and go to f-- bed, d--. B--, I told you to stop feeding that dog human food. Go to bed!"

"Stop lying to me," she said. "I know you gave it to her. Go to bed and shut the f- up."The older woman shuffles to her walker, but Floyd gets in her face, demanding an answer. Bratten stammers that she didn't do it, but Floyd cuts her off.

The yelling and hitting continued as the two women walked out of the room.

On a wall opposite Bratten's easy chair, a camera captured the entire interaction. Her family had suspected abuse, police say; the New Year's Day video gave them proof.

Floyd is charged with elder abuse, a second-degree felony, and investigators are trying to determine whether similar incidents have happened in the past to Bratten, who has difficulty speaking. Floyd has taken care of Bratten for three years and worked as a caregiver for 15, Memorial Villages Assistant Chief Ray Schultz told The Washington Post.

Floyd had lived in the home in Memorial Villages, just outside Houston, tending to Bratten's needs six days a week. The 59-year-old had grown close to her patient's family. They had even helped her buy a car, Schultz said.

But in recent months, the woman's adult children found bruises on their mother.

"They had seen bruises for a while - at least for a couple of months," Schultz said. "But it was nothing really massive or crazy. The bruises that they would see would be underneath her arm, like if someone was helping you get up. They had talked to the mother, but her communication is almost nonexistent."

Suspicious, her son installed a nanny camera on New Year's Eve. He hid it in the living room, facing the chair where his mother often sat to watch television and eat meals.

The day after the alleged assault, he was reviewing the video and saw the alleged attack on his mother. He sped to the house, confronted Floyd, fired her and called police, according to police.

But Schultz said his police department wanted to consult with the district attorney and attempt to interview Bratten in a calm setting before they made an arrest.

Floyd "gave us a story basically admitting that she did hit her, but she said she kind of tapped her, to get her to wake up for a bath."

When they went to arrest Floyd a few days later, she had disappeared.

Houston Crime Stoppers announced a reward for information leading to Floyd's arrest and released the video on YouTube this week.

It was aired on the local news and seen by millions. And tips began flooding in.

"She's anybody's grandma," Schultz said of Bratten. "A lot of people have kind of adopted her. We've been getting flowers, and received phone calls. People were definitely very upset and disgusted."

Early Friday, police got a useful tip: Floyd was at an apartment in northern Houston. The Lexus Bratten's family helped her buy was parked outside. Officers knocked on the door and Floyd was arrested without incident.

She was released on $5,000 bail, police say. She couldn't be reached for comment Friday and it was unclear whether she had hired an attorney.

According to the National Council on Aging, one in 10 Americans over 60 have experienced some form of elder abuse, and some estimates say there are 5 million victims each year.

It's worse for people who have some form of impairment, according to NCOA.

"Recent studies show that nearly half of those with dementia experienced abuse or neglect," the council says. "Interpersonal violence also occurs at disproportionately higher rates among adults with disabilities."