stacey , now 20 , helped her mother care for her throughout her teenage years .
but after eight years of battling the condition , they cared for her and began to live with the disease .
but though she had experienced enough grief , stacey johnson was soon another cruel blow - doctors discovered her younger sister dannii also had a growth in her brain .
stacey , now 22 , was diagnosed with an inoperable tumour in 2007 and has undergone gruelling rounds of chemotherapy and radiotherapy .