It was a pastime that helped her get through the year and now, ten years later, has grown into a significant fundraiser for the hospital.
At the end of her stay in hospital, Ruby's mother had one of the designs in her notebook turned into a tea-towel.
The tea-towels sold so well, they did the same thing with another design the following year.
The year after that Wallace Cotton came on board and, eight designs later, Ruby's tea-towels have now raised an incredible $400,000 for the Starship Foundation.
"It is so rewarding to give back to the amazing hospital that helped me get better, connecting with children who are going through their own tough journey," she said.
This year Ruby returned to Starship to launch her latest fundraising tea-towel "Watermelon ice pops for Starship".
The new design incorporates a recipe for watermelon ice blocks with edible flowers.
There's also a colouring-in version complete with fabric markers so children can add their own creative twist.
Money raised from the sale of the tea towels and Nice Blocks will help establish an ovarian tissue cryopreservation banking protocol for New Zealand Paediatric Haematology/Oncology Services, to benefit young cancer patients.