Image copyright Reuters Image caption The couple were barred by the judge from contacting their 13 children

A judge in California has issued a protective order banning the parents of 13 siblings allegedly held captive in a suburban home from contacting them.

David and Louise Turpin, appearing shackled in court, must stay 100 yards away from their children and have no electronic contact for three years.

The Turpins have been charged with multiple counts of torture, false imprisonment and other charges.

The couple has pleaded not guilty to the charges against them.

A former classmate of the couple's eldest daughter has said she was relentlessly bullied in school.

Taha Muntajibuddin described her in a Facebook post as "a frail girl" who wore the same purple outfit every day.

Mr Muntajibuddin, who attended nursery with her in Fort Worth, Texas, wrote that he felt "an overwhelming sense of guilt and shame" when learning about the conditions his former classmate experienced at home.

How can parents torture their children?

He wrote: "You can't help but feel rotten when the classmate your peers made fun of for 'smelling like poop' quite literally had to sit in her own waste because she was chained to her bed."

Mr Muntajibuddin, who realised he went to Meadowcreek Elementary School with the eldest daughter when reading the news of the Turpin case, described her clothes as looking as though they had been dragged through mud.

"It is nothing but sobering to know that the person who sat across from you at the lunch table went home to squalor and filth while you went home to a warm meal and a bedtime story," Mr Muntajibuddin wrote.

Image copyright Getty Images Image caption Louise Turpin, 49, appears in court at her arraignment with husband David on 18 January 2018

He said the eldest Turpin child was often called the "cootie kid" and teased continually by her classmates.

"I distinctly remember my entire third grade class scoffing at her one day because our teacher had asked her to discard a scrunchy she had used to tie her hair out of a discarded tin foil wrapper from an old Hershey's bar," he said.

The eldest son of Turpins reportedly attended classes at a community college in San Jacinto, California, where a classmate has described him as withdrawn and visibly hungry, according to a local media.

Angie Parra, a classmate at the Riverside County college, told NBC Los Angeles the young man was "sweet but odd" and always wore the same clothes.

According to ABC News, the unnamed Turpin son had achieved a 3.93 grade point average, equivalent to an A grade.

The 13 siblings were allegedly kept in squalid conditions in their home, often chained to beds and unable to use the toilet, until the couple's 17-year-old daughter escaped on 14 January and alerted the authorities.

It has been reported in local media that the Turpins were due to move within days of the daughter's escape.

Mr Turpin, 57, was said to have received a job transfer to Oklahoma with a defence contractor, Northrop Grumann.

The 'happy family' at centre of torture allegation

About 20 people from across the country, including nurses and psychologists, have offered to care for the seven adult siblings and six children.

The Riverside University Health System Foundation, which is collecting donations for the children, has received 1,500 contributions that total $120,000 (£84,400), according to spokeswoman Kim Trone.

Prosecutors detailed some of the horrific allegations against the parents in a news conference, including frequent beatings of their children, only allowing one shower a year, and keeping them chained to their beds.

Media playback is unsupported on your device Media caption Shackled siblings: What we know about their lives

The siblings, age two to 29, were found in an emaciated state by authorities in their home in Perris, according to police.

Officers had at first thought all the children were minors until they realised some were frail and malnourished adults.

Mr Muntajibuddin said that despite being bullied, the Turpin girl "was still one of the most pleasant people I have had the opportunity to meet".

"She had this whimsical optimism to her that couldn't be dampened, couldn't be doused no matter what anybody threw at her," he added.

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If found guilty of the dozens of charges against them, the Turpin couple could receive 94 years to life in prison.