Dannii Minogue said her older sibling has been asked to extend her current US tour to play in the gambling resort after her first full American tour was well received.
The X Factor judge said: "The response from her shows in America have been phenomenal. They love her out there. She was nervous about going over for the first time, but it has gone better than she expected.
"She has now been asked to take the show back to Vegas and extend it as a residency over there. I'm so proud of her."
She added: "She called to tell me how well everything has been going and about the Vegas offer. I was joking with her that The Showgirl is finally where she belongs.
"Kylie's show is perfect for Vegas, it's so theatrical. She has loved performing out there."