Diagnosed in May 2005, Kylie underwent a lumpectomy and chemotherapy, and in a recent interview on ABC's Take 5, Dannii has discussed the impact her sister Kylie's cancer battle had on her.
"My sister got sick with breast cancer and she was in the middle of a tour." She choked up as she continued: "I remember her getting carried off stage and stuff. When I would go and visit her when she was having chemo and was very, very unwell. I would just jump around to music with her," she said.
"It was music that kept us going and she was like, 'I need to finish the tour!' Like, she's so professional. We were like, 'Oh for god's sake, we need to keep you alive!' We knew that was her goal to get back and honour all those tickets. Every single person kept the ticket."
The 52-year-old went on to discuss Kylie's return to stage after completing chemotherapy in January 2006.
"She said, 'Will you jump on stage with me?'... And the joy when we came out on stage from the audience was unbelievable. You could hear the roar."
In the vulnerable interview, Dannii also touched on how one of her closest friends, Laura, also battled cancer but sadly passed away.
"She was staying with me and said she had pain in her back. An hour later, she was in the foetal position. She went into hospital and she never came out again. It was very hard to see her go through this."
Dannii admitted that watching two women so close to her going through cancer was a dark time for her, but attributes the support of her sister Kylie for helping her navigate it.