The mother of murdered Melbourne teenager Prue Bird has begged Bega schoolgirl killer Leslie Camilleri to reveal where her daughter's body is buried.

Jenny Bird shook uncontrollably as she told Camilleri she had wished every day she could end her life since her 13-year-old daughter disappeared from their Glenroy home in 1992.

Camilleri, 43, has pleaded guilty to Prue's murder but has refused to reveal where her body is or give details about what happened to her.

"Please, Les," Ms Bird pleaded in the Victorian Supreme Court on Wednesday.

"The constant pain in my chest is my broken heart.

"I have prayed for cancer to take me. I would not care if I died tomorrow.

"I pray every night that you will give me my little girl so I can bury her.

"Please, Les, please listen. I just want my little girl back."

Justice Elizabeth Curtain again urged Camilleri, who has converted to Islam, to reveal where he had buried the body.

"If you can at all find it in your heart or conscience, you now being a person of faith, to disclose the identity of where Prue Bird's body can be found, then you should do that," she said.

"You're the father of four children yourself.

"You have a think about how you would like to be in Ms Bird's position, let alone the fact that by your plea of guilty, you acknowledge that you put her there."

Camilleri remained expressionless and silent.

He will be sentenced on a date to be fixed.