A friend of Amy "Dolly" Everett says she has been left asking whether she could have done anything to prevent the 14-year-old's suicide.
Taniesha Southeron says she and others have been questioning themselves after Dolly's death this week, which her family have linked to cyber bullying.
"I think everyone who knew Dolly when they found out what happened they would have asked themselves, 'was there something I could do?'" Ms Southeron told the Seven Network.
"Did I miss something? Did I not see something? Did I say something wrong? Has she taken something I've said in the wrong way? It's very hard for all of us. I know we've all ask ourselves those questions."
Dolly will be farewelled in a public service at the Casuarina Street Public School in Katherine on Friday, with supporters urged to wear her favourite colour blue.
Her family have also called for donations to a new foundation called Dolly's Dream, aimed at supporting young people, and the 14-year-old's father Tick earlier this week called on his daughter's bullies to attend.
"Please come to our service and witness the complete devastation you have created," Mr Everett wrote on Sunday.
His daughter's death has sparked a battle cry among concerned parents and others, prompting a Queensland mother to launch a campaign to shut down an app that was used to bully her own daughter.
"I do not want my daughter or any other to become the next Dolly," Katrina wrote in the change.org petition, which has already received more than 31,000 signatures.
The Rockhampton mother, known only as Katrina, has called on Apple's App Store and Google Play to stop downloads of Sarahah, which allows people to leave anonymous feedback for each another.
Sarahah's website says the app, "helps you in discovering your strengths and areas for improvement by receiving honest feedback from your employees and your friends in a private manner".
Katrina says her daughter doesn't have the app, but was "shattered" after seeing a message written about her.
"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," Katrina told The Courier-Mail.
Prime Minister Malcolm Turnbull has also seized on Dolly's death to call for more action on cyber-bullying.
"Every step must be taken to reduce the incidence of bullying, whether offline or on, and eliminate it wherever we can," Mr Turnbull wrote in a comment on Facebook.
Northern Territory Police confirmed they are investigating the circumstances surrounding Dolly's death.
"NT Police can confirm they're investigating all the circumstances surrounding the non-suspicious death of a 14-year-old girl. A report will be prepared for the Coroner," a police spokesperson said.
Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14.
Suicide Call Back Service 1300 659 467.
Kids Helpline 1800 55 1800 (for young people aged 5 to 25).