Last week, 14-year-old Dolly took her own life after being "overwhelmed" with cyber-bullying.

A devastated Northern Territory family has spoken out against online bullying after their 14-year-old daughter took her own life.

Amy Everett, who her family called Dolly, died on 3 January after she was “overwhelmed” by cyber-bullying. The teenager had previously been the face of ad campaigns for iconic Australian hat brand Akubra.

Just four days after her death, her father, Tick Everett, penned a heartbreaking Facebook post thanking people for their support and urging them to help stamp out bullying.

“This week has been an example of how social media should be used, it has also been an example of how it shouldn’t be,” he wrote.

“If we can help other precious lives from being lost and the suffering of so many, then Doll’s life will not be wasted.”

Tick said his “precious little angel” had died by suicide to “escape the evil in this world”.

Dolly. (Image via Facebook.)

"However, unfortunately, Dolly will never know the great pain and emptiness left behind," he wrote.

The heartbroken father also issued a challenge to those who "thought this was a joke and made themselves feel superior by the constant bullying and harassment" to come to Dolly's funeral service on Friday and "witness the complete devastation you have created".

Dolly (right), her sister Meg, mum Kate and dad Tick. (Image via Facebook.)

"The second [challenge] is for the strong ones. Let's stop the bullies no matter where, but especially in our kids. As the old saying goes: You will never know what have until it's gone."

On Wednesday, Akubra Hats penned their own Facebook tribute to Dolly, sharing a photo of Dolly taken when she was six and featured in their Christmas advertising.

The company also spoke of the sadness their staff experienced at this loss and urged anyone reading to be there for one another in an effort to prevent others from the same fate.

"To think that anyone could feel so overwhelmed and that this was their only option is unfathomable,"

"Bullying of any type is unacceptable. It is up to us to stand up when we see any kind of bullying behaviour.

"Dolly could be anyone's daughter, sister, friend. We need to make sure that anyone in crisis knows there is always someone to talk to. Be a friend, check up on your mates."

"Our hearts go out to her family and friends."

Dolly's funeral will be held on Friday at a local primary school in Katherine East. Tick, along with Dolly's mum Kate and sister Meg, encouraged those attending to wear her favourite colour, blue.

If you or anyone you care about is experiencing suicidal thoughts and would like support, there is always help available. You can call Lifeline on 13 11 14, the Suicide Call Back Service on 1300 659 467, Kids Helpline on 1800 55 1800 or BeyondBlue on 1300 22 46 36.