The sibling pimps — both with IQs in the lowest one per cent of the population — had to be brought up by their grandmother because their heroin-addicted mother spent 26 of the past 30 years in jail.

The whole sad and sordid story can today finally be revealed by The Daily Telegraph after the sisters and four of their customers were convicted in the District Court.

The grubby underworld of sex slaves as young as 12 was exposed by Liverpool detectives investigating what they thought was a simple $500 robbery reported by disgraced accountant Rino Mura.

The 58-year-old called the cops after he was robbed at knifepoint while in his vehicle in a Western Sydney carpark in February 2012.

Suspicious detectives set up Strike Force Woodvale, led by Detective Sergeant Christie Houlden, and discovered Mura had been sitting in his car at the time with a 13-year-old prostitute who had been advertised as “very pretty, size 10, big boobs, black hair”.

Mura was a regular client of the sisters, who cannot be identified, and they had set him up to be robbed by one of their friends.

Detectives soon learned the sisters had been running their business for three years from the ages of 16 and 19 from their Warwick Farm housing commission unit.

They convinced girls to act as sex slaves through mutual friends or on Facebook and lured them with the offer of a bed in the sisters’ flat and the promise of drugs like ice.

Sometimes they were pimped out for the price of a pack of nappies for one of the older sister’s three young children.

Some of the girls put on heavy make-up to look older and were put to work in the backs of cars or grubby motel rooms, such as the Grandstand Motel in Warwick Farm, rented out for $49 for half a day. Others were threatened with violence if they did not have sex with the siblings’ “old, bald or fat” clients.

One girl was told she would be back out on the streets in the pouring rain if she did not “sell herself”. Another said she closed her eyes and cried during the sex sessions. The 12-year-old was pimped out to three different men over three days.

“I was so alone,” another of the child prostitutes, aged 13, told a court.

“I still live in fear of being kicked out into the streets, having nowhere to go and no one to love me.”

Mura was convicted of three counts of being a client of a child prostitute aged between 14 and 18 and two of possessing child porn. He is due to be sentenced in the District Court today.

The courts have been told how the sex ring devastated the families of its clients as well as the lives of the victims. One client, crane driver Bassam Darwich, 57, is a father of six. One of his young victims “lay there crying ... placing the pillow over her face until the sex had finished”.

Darwich was jailed for three years and six months with a non-parole period of 20 months. The Court of Criminal Appeal last week reserved its decision after a Crown appeal that the sentence was “manifestly inadequate”.

Trevor Andrew Weger, 56, of Canley Vale was convicted of four counts of being the client of a prostitute aged between 14 and 18 and jailed for three years.

ET, a 61-year-old Iraqi immigrant with two adult daughters, was sentenced to one year and eight months to be served as an intensive corrections order.

The oldest sister pleaded guilty to 21 counts of child prostitution and was jailed for eight years with a minimum term for six years. Her three children are in care. The younger sister pleaded guilty to 10 counts and was jailed for six years and 10 months with four years’ non-parole.

“Children are entitled to the protection of the law even when they are not protecting themselves,” Judge Martin Blackmore said in sentencing ET.