"Speak even if your voice shakes", he said, quoting a caption from a sketch of a dancer that Dolly had recently drawn.
Mr Everett said the family would remember Dolly "as a kind, gentle and loving little girl ..."
"It won't bring our Dolly back, but it may just prevent the loss of another young life".
Dolly's parents expressed gratitude for the "overwhelming response" they received to their grief and asked for time to celebrate the life of their lovely daughter.
Amy Jayne Everett, also known as "Dolly", became the face of iconic Australian outback hat maker Akubra when she was 8-years-old.
In 2016, The Sun Online launched its Block The Bullying Campaign with the NSPCC in a bid to stamp out the sharing of vile videos showing children being attacked.
Dolly's Warwick-based school Scots PGC College, southwest of Brisbane, flew its flag at half mast today and will host a commemorative service in term one. Right: Dolly at her home in Katherine. Did I not see something? It's very hard for all of us.
"If by some chance the people who thought this was a joke and made themselves feel superior by the constant bullying and harassment see this post, please come to our service and witness the complete devastation you have created", Tick Everett wrote on Facebook Sunday.
Since reading sickening the abuse sent to her daughter through Sarahah, the mother says she's been "scared, broken and sick to her stomach".
Tick Everett urged parents to talk to their children.
"Dolly, you are loved and you will never be forgotten, " he wrote.
Sarahah's website said 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".
'My daughter and I have been shattered by this app, and tragically another teenager, in the United Kingdom, was found hanged early in 2017 after allegedly being bullied on a similar app called Sayat.Me, which was shut down in May'.
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.
Northern Territory Police are now investigating Dolly's death and whether cyber bullying was a factor. Even though suicide is the top cause of death for 15- to 44-year-olds in Australia, it isn't discussed much in public, in part because media outlets fear that reporting on self-inflicted deaths will trigger more suicides. "We need young people to report it to a trusted adult".