Witchcraft, snakes, satanic rituals and Ouija boards: Louise Turpin’s sister says she was “freaked out”.

Warning: This article contains information about child abuse which may be distressing for some readers.

In January this year, Louise and David Turpin were arrested and charged with nine counts of torture and 10 counts of child endangerment.

The arrest came after the couple’s 13 children – ranging in age from two to 29 – were found living malnourished in horrifically filthy living conditions.

It was alleged that the children were starved and some were kept chained and shackled to their beds. The children were allegedly beat and strangled and their parents only allowed them to eat once a day and shower once a year.

The children, including the adult children, appeared to know little about the outside world – some of the children did not know what medicine was, for example.

The arrest of David and Louise was made after the couple’s 17-year-old daughter escaped from the home and called the police.

The 17-year-old girl who called the police was so malnourished, police thought she was no older than 10 years old.

Louise Turpin’s sister, Elizabeth Flores has written a book about her sister and the case titled Sister of Secrets.

In the book, Elizabeth alleges that Louise’s obsession with witchcraft may have fuelled the alleged child abuse.

Although Elizabeth says she had no knowledge of the conditions the children were living in, she believes that her sister's prior obsession with Satanic rituals and Ouiji boards may have had something to do with it.

“She told me she was messing around with witchcraft. It just really freaked me out,” Elizabeth told the New York Daily News in an interview.

“She brought the Ouija board to my home and I wouldn’t let her bring it in my door," she said.

“I do know witchcraft is very serious and demonic. If she did get deep into that, I do think it could have led her to do what she did because you’re basically selling your soul to the devil,” Elizabeth added.

She also revealed that Louise had an obsession with snakes, after reading that "snakes give you power".

Elizabeth visited the Turpin home after the arrest, where she saw a snake statue at the front door.

“Louise was attracted to that, like women dancing with rattle snakes around their necks,” Elizabeth told the Daily News.

The two sisters haven't had "a sister relationship" for a few decades, besides the occasional phone call.

In the book, Elizabeth also wrote about Louise's childhood and how her sister changed when David entered the picture when Louise was just 15.

“You don’t want to believe that your sister would torture anybody,” Elizabeth wrote.

On the topic of their childhood, Elizabeth has previously claimed that she and Louise were sexually abused as children by a close family member.

She has also previously admitted that David watched her shower when she briefly lived with her sister and her husband when she was 20 years old.

David and Louise Turpin, who are being held on $12 million bail, have both pleaded not guilty to their charges.

A preliminary hearing is scheduled for the couple on June 20.