A woman who is a drug addict allowed her 13-year-old daughter to be sexually assaulted by a truck driver. She will be spending nearly five and a half years in prison.

Both the woman and the man who assaulted the young girl have been sentenced by Sydney's Downing Centre District Court.

There were indicted by a jury of various charges, including sexual and indecent assault on the young girl on almost three occasions.

It was confirmed by Judge Greg Woods that the woman is a heavy drug user and she mainly used illegal drugs like ice and cannabis. The truck driver was aware of her dependence on drugs and took advantage of her condition. The woman also pressed her young daughter into having sex with the man.

The woman will not be eligible for release before December 2012. The man who had sex with her daughter will not be eligible for release before October 2017.

The court heard that the man who is aged 31 was of good character. He was also involved in a sexual relationship with the woman and they are also charged for forcing the girl to watch them perform sexual acts.

The woman was severely criticized for her actions and putting the welfare of her daughter in danger.