The 64-year-old Newton-John, herself a survivor (she was diagnosed with breast cancer nearly two decades ago), put recent plans to headline Las Vegas's Flamingo Hotel on hold when she heard that older sister Rona, 69, had the disease.
"As a cancer 'thriver' myself, as many people are, I am very aware of the importance of love, support, and family during this journey she is about to begin," Newton-John said in a statement to "Entertainment Tonight."
She then thanked fans and asked for the family to have privacy at this time.
The Las Vegas Sun revealed last week that the legendary Grease star was slated for a mini-residency at the Flamingo starting this summer, sharing alternate dates with Donny and Marie Osmond. There's no word if or when she plans to reschedule her appearances.
- breast cancer