"To this world's most precious and beautiful girl – My dear sweet friend Hannah," the message read.
"I can scarcely believe it's been just a few weeks since you so tragically left us, the splitting of our hearts deafeningly loud, and the ache of your absence is so heavy it's hard to bear.
"How could this world keep turning without you and our little angels? Writing this letter, I wanted to list all the amazing memories since we first met at the local PCYC when you were 14 and I was the big girl 16!
"But sadly, there would never be enough space!
"You always made me laugh even when I knew deep down you were hurting more than any of us could imagine.
"Over the years we sure made some mischief, but we always had each other's backs.
"Remember the time we came home after a few drinks and straightened dad's hair while he slept!
"Or the time you were the sober one, and you bunny-hopped us home not knowing how to drive my manual car!
"You had an irony to your wit, and that smile today even with you gone is resonating across communities far and wide – the beautiful mum and her three little miracles taken from us by someone I refuse to acknowledge.
"I don't know what I ever did to deserve you – I only know your friendship was my home.
"You carried the weight of the world on your shoulders, and we all wish now we could've lightened your load.
"I'm sorry I couldn't protect you. My gorgeous Tim and our boys, Ryder (7) and Brooklyn (4), will be blessed forever knowing your girls, Aaliyah (6) and Laianah (4), will always be our boys' besties.
"When your little Trey (3) came along, I loved how the older ones always held his hand and guided him down their paths of adventure.
"Those lasting memories will always be with us from New Year's Day this year when you and the kids and your mum and dad, all of us on the beach with not a care in the world.
"We prayed this was the beginning of your new life of freedom – sadly, that was never to be.
"You really were made of equal parts stardust and sass – and you lit up lives as if shining was what you came here to do.
"That light will shine forever in the next place you go.
"I'll never forget you my brilliant friend – for now I'll just bask in your afterglow until we meet again.
On February 19, as Clarke's children were on their way to school, her estranged husband, New Zealander Rowan Baxter, forced his way on to the front passenger seat and doused his family in petrol before setting them alight.
The children, safely strapped into their child restraints, never stood a chance. Hannah was on fire as she leapt from the driver's seat screaming, "he's poured petrol on me" as people tried to put out the flames.
With burns to 97 per cent of her body, Hannah died in hospital hours later.
Baxter died on the footpath after stabbing himself.