Billy Lambert says he and his siblings were outraged to learn about the allegations against sister Louise, 49, and her 56-year-old husband, David Turpin

Brother of Mom Accused in House of Horrors: 'If We Knew, We Would Have Stopped it Ourselves'

The half-brother of Louise Turpin, the mother accused of abusing her 13 children in a house of horrors in California, says he has been harassed by strangers who believe he and his other siblings were aware of the years of alleged violence.

“We have had numerous people sending us crazy messages that we knew,” Billy Lambert tells PEOPLE. “If we knew, we would have stopped it ourselves.”

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Lambert, 30, says he and his siblings were outraged to learn, over the internet, about the allegations against his sister Louise, 49, and her 56-year-old husband, David Turpin, who were arrested early last week in Perris after one of their kids called 911.

The Turpin children, who range in age from 2 to 29, were found malnourished, according to authorities. They suspect the kids were beaten, strangled and kept captive in their home — shackled to the furniture — in a cycle of intensifying abuse dating back at least to 2010.

Only the youngest child, it seems, was somewhat spared.

Both David and Louise face a dozen charges each of torture and false imprisonment, among other counts. “It appears no one noticed what was happening,” prosecutor Michael Hestrin told reporters on Thursday.

“It was more than just a shock — it was devastating to us,” Lambert tells PEOPLE of the accusations. “She would tell us the kids are doing great. She was real busy home-schooling. She told us David was making two or three hundred thousand [dollars] a year, so we thought they had this awesome life and always going on trips.

“We didn’t never in a million years think that something like that was actually going on.”

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Image zoom The Turpin family David-Louis Turpin/Facebook

Image zoom From left: David and Louise Turpin Riverside County Sheriff's Department (2)

Lambert says that the day his 17-year-old niece escaped the Turpin home and notified authorities — Jan. 14 — was already a special one in the family.

“It was their grandmother’s birthday, but I honestly don’t know if they knew that,” he says. “It is crazy that she got away that day.”

Lambert, who described his sister as outgoing and David as “always trying to make me laugh,” says he last spoke to Louise on Jan. 10. He says she told him she had plans to have a 14th child and David was looking to buy a school bus to accommodate the growing family.

“She had mentioned the Kate Plus 8 show, that it was a cool reality show,” he says. “I think deep down that is what she wanted [a big family]. She said her doctor said it was fine [to have another child]. To me it was strange.”

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Lambert says he asked to speak to his nieces and nephews on numerous occasions over the years, but Louise always found an excuse why he couldn’t. In one instance, he says, his sister was driving to pick up her oldest son at college and he asked to speak to his nephew and “she said, ‘Yes, when I go get him I can let him talk to you,’ ” he recalls.

“She didn’t call me back. If we asked to talk to the kids, she would always make an excuse and blow it off.”

Both Louise and David reportedly grew up in Princeton, West Virginia, and they married in 1985 before eventually relocating to Texas. Their first child was born when Louise was 20, Lambert says.

According to investigators, the Turpins lived in Texas for 17 years and then moved first to Murrieta, California, in 2010, and then to Perris, in 2014.

Image zoom The Turpin home in Perris, California Sandy Huffaker/Getty

According to Hestrin, the Riverside County, California, district attorney, the children were regularly chained to their beds and deprived of food, the use of the lavatory and daily showers.

David and Louise was charged last week with with 12 counts of torture, seven counts of abuse of a dependent adult, six counts of child abuse or neglect and 12 counts of false imprisonment for crimes dating back to 2010. David was also charged with one count of lewd act on a child under the age of 14 by force, fear, or duress.

Both pleaded not guilty to all charges and remain in custody. If convicted, each faces up to 94 years to life in prison. Their attorneys declined to comment on the case beyond broad reactions to the allegations.

“I hope they give her life without a chance of parole or anything,” Lambert says of Louise. “I don’t think she should have any contact with the kids because of the way she treated them.”

About his nieces and nephews, Lambert says: “I am glad they got out. I think they are an inspiration to other kids who are in that situation. You can get away and get help.”