A QUEENSLAND mum whose 13-year-old daughter was encouraged to kill herself by "vile" online trolls is calling for an anonymous posting app used by young bullies to be shut down.
The Rockhampton mother said the app, called Sarahah, allows people to leave anonymous comments, and had been used to bully her daughter.
She discovered the cruel comments just days after the suicide of 14-year-old Queensland schoolgirl 'Dolly' Amy Jayne Everett, who was also bullied online.
Northern Territory Police are now investigating Dolly's death and whether cyber bullying was a factor.
"My daughter doesn't even have this app but these bullies sent it to her friend about her saying she should kill herself and that everyone would be so much happier and that everyone hates her," said Katrina, who The Courier-Mail has chosen not to identify.
"This app is just creating another avenue for these gutless warriors to come and take advantage of people in a delicate fragile state and it's horrible."
About 6000 people had signed an online petition calling for the app to be shut down last night, bolstered by the outrage over Dolly's death.
"It's unthinkable to fathom what would have happened if we didn't find out," she said.
The condemnation of bullies and outpouring of grief at Dolly's death saturated social media this week, with people from Canada to London promising to wear blue today in honour of the Australian country girl with a heart of gold, who will be laid to rest in Katherine today.
Cyber safety experts have also pleaded with Queensland parents to be on the lookout for warning signs of bullying with the school year just two weeks away.
Alannah & Madeline Foundation senior cyber safety adviser Jeremy Blackman said one in five children experienced bullying and one in seven suffered cyber bullying.
"If cyber bullying is happening, in about nine out of ten cases it's also happening concurrently offline," Mr Blackman said.
"Because of anonymity online, it does make it easier for anyone to be a bully."
Capricornia MP Michelle Landry, who will be one of the politicians to receive Katrina's petition, welcomed the push to stamp out anonymous posting apps.
"If someone can't put their name to a statement, it isn't worth reading, but not everyone knows that, and the fallout is too awful to contemplate," she said.
"I wholeheartedly support Katrina's quest to keep our kids safe and will be in her corner for the fight."
A spokesman for Scots PGC College refused to say whether Dolly's bullying would be investigated, saying its focus "remains on supporting Dolly's family and our community during this extremely difficult time".
Northern Territory Children's Commissioner Colleen Gwynne has called for an investigation amid growing concerns over the affect social media bullying is having on teenagers' mental health.
The attack on Katrina's daughter has been reported to police.
If you, or someone you know, needs help: Lifeline 131 114, Kids Helpline Official 1800 55 1800, Beyond Blue 1300 22 4636