A young mother and her boyfriend have been charged with injecting her three children with heroin and telling them it is 'sleeping juice' in their squalid home.

Ashlee Hutt, 24, is accused of plying her two daughters and son, aged six, four and two, with the drug at their house in Spanaway, Washington.

Her boyfriend, 25-year-old Leeroy 'Mac' McIver, is also accused of drugging the children.

Police discovered the children living among rat droppings and dirty needles when they visited the house last year after being alerted to the situation by one of the couple's friends.

Ashlee Hutt, 24, is accused of injecting her two young daughters (above) and son with heroin

The children were all removed in November last year, six months after CPS launched an investigation into their care, Kiro 7 reported.

It is not clear if McIver is the children's biological father. All three of the children are now living in foster homes.

Child Protection Service officers noticed scratches, bruises and markings on the two-year-old girl's body which suggested she had been injected with the drug.

They interviewed her older brother who described how his mother and her boyfriend would 'mix white powder with water' and inject them with it.

On one occasion the boy said he was given the drug after being choked by McIver.

He said he and his siblings would fall asleep afterwards and that his mother referred to it as 'feel good medicine' and 'sleeping juice', The News Tribune reported.

They found traces of heroin in the two-year-old girl's hair follicles after she had been removed from the house.

Another one of the children tested positive for the drug but one did not. Hutt was arrested on November 12, 2015, when officers visited the home.

The young mother's boyfriend, Leroy 'Mac' McIver, is also accused of drugging the children

Hutt (left at her arraignment on Monday in Tacoma) remains in custody. Police were alerted to the family by a friend who visited the house

The house where the family lived was found to be infested with rat droppings and needles

The young mother is charged with three counts of unlawful delivery of a controlled substance to a minor, second-degree criminal mistreatment and second-degree child assault.

Hutt's six-year-old son (above) told police how she called the drug 'feel good medicine' and 'sleeping juice'

McIver faces the same charges. The pair both admit to being heroin addicts.

They both remain in custody. Hutt was arraigned on Monday in Tacoma, her boyfriend was arraigned last month.

Neighbours said police often visited the home.

Neither Pierce County Sheriff's Office nor Washington State's Child Protection Services could confirm whether they had received concerns for the children's welfare before Hutt's November arrest.

Two years ago Hutt celebrated the jailing of another mother in the town whose baby died after drinking bong water.

Alyia Iverson's son Nathan died from a methamphetamine overdose in 2012. He had been allowed to drink bong water before his death.

'Finally justice for you,' she said, sharing a photograph of the infant on social media.

Hutt claimed she knew the baby and rejoiced when his mother was jailed.

'It's heart breaking that you had to lose your life due to the state not listening.

'This never would've happened if you were with your father or family that actually cared for you.'

The two-year-old girl was found to have traces of the drug in her system when her hair follicles were tested