Two half-siblings from Virginia on Wednesday were handed combined sentences of more than 100 years for sexually abusing two young girls in what has been described by prosecutors as one of the most disturbing cases they have ever encountered.

Robert Eugene Clark, 39, was found guilty of nine counts of rape, aggravated sexual battery and taking indecent liberties, and sentenced to 65 years in prison.

Samantha Kay Simmons, 30, was convicted of 11 counts of aggravated sexual battery, sodomy and endangering the welfare of a child, and given a prison sentence of 43 years.

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Robert Clark (left), 39, was found guilty of nine counts of rape, aggravated sexual battery and taking indecent liberties, and sentenced to 65 years in prison. His half-sister Samantha Simmons (right), 30, was convicted of 11 criminal counts and sentence to 43 years

The victims in the case were two sisters, aged 3 and 8, who were discovered in 2015 living in a filthy trailer crawling with myriads of cockroaches and littered with human feces.

The investigation got under way in early September of that year when a Rockbridge County Sheriff's deputy pulled up to a mobile home on Jasmine Lane, shared by Simmons and Clark, to perform a check at the request of a neighbor who had expressed concern for the welfare of the two girls living there reported The Roanoke Times.

The deputy wrote in his report that approaching the residence, he was struck by the stench of urine and observed insects swarming all over the trailer.

When he crossed the threshold and stepped inside the living space, he saw what appeared to be thousands of cockroaches and other bugs on the walls, the ceilings, the floor and all the furniture.

The deputy then saw a 3-year-old girl who, as he later reported, was crying while seated at the kitchen counter, with insects crawling all over her.

That trailer, and another mobile home located nearby where the victims' grandmother lived, reeked of human feces and were infested with insects.

The abuse came to light in 2015 after a Rockbridge County Sheriff's deputy pulled up to a mobile home on Jasmine Lane (pictured) to perform a welfare check

One of the homes was crammed with piles of refuse 2-3 feet high, and there were pornographic materials and guns scattered in plain sight and within easy reach of the children.

The deputy's report about the shocking living conditions eventually led to the toddler and her sister, then aged 8, being removed from the household of Clark and Simmons and placed in a foster home.

On the day the younger girl was rescued from the filthy trailer by social workers, she was wearing just a diaper and was caked with dirt. She could only utter two words - her older sister's name and 'no.'

Peggy Sigler, a caseworker with the Rockbridge Area Department of Social Services later testified that the 3-year-old was a 'feral' child.

Sigler inspected the family's' two mobile homes in September 2015 after getting reports of child abuse and found the living conditions deplorable.

‘You walked in the home and the cockroaches would literally jump on you and crawl all over your body,’ she testified.

When she opened the refrigerator, Sigler said she found cockroaches all over the food that was inside.

In May 2016, eight months after she was removed from the bug-infested trailer, the older of the two sisters revealed to her foster mother that in the course of four months in 2015, Robert Clark repeatedly raped and sexually abused her and her 3-year-old sister, forced them to perform sexual acts on one another and whipped them with a belt while they stood naked.

Simmons and Clark lived with the two girls, aged 3 and 8, out of two trailers tat were crawling with bugs and were filled with trash

The girl also said they were shown pornographic movies and she often bled from the abuse, reported the station WSET.

‘There’s no other way to describe this than as a family orgy,’ Chief Deputy Commonwealth’s Attorney Jared Moon said this week.

Nearly two years later, the two sisters are doing better and getting ready to be adopted by their foster parents, but the younger girl, now aged five, still suffers from developmental problems and has trouble learning words and numbers; of all the colors, she can only identify purple, according to the newspaper.

The local department of social services has come under fire for allegedly failing to promptly act on reports of abuse in this case, and in some instances ignoring complaints from concerned neighbors.

A supervisor at the agency eventually resigned after it emerged that she refused to enter some complaints into the agency’s computer system in violation of state policy and shredded others.

According to a grand jury report, the manager was quoted as allegedly saying of the two abused sisters, 'they're used to living that way so what's the big deal?'

The grand jury declined to bring any criminal charges against the ousted supervisor.

Meanwhile, Clark and Simmons’ defense attorneys argued in court that the half-siblings themselves had been the victims of sexual abuse as children.

Simmons' attorney likened her to a 'quivering rabbit' who was incapable of recognizing the deviancy in her actions, while Clark’s lawyer said his client has a mild form of mental retardation.

When given a chance to speak before sentencing, Clark said he does not mind spending his life in jail, so long as he has a roof over his head, a bed to sleep on and three meals a day.