The former rugby league star is said to have proposed to the mother of his son, Ethan, over the phone from Melbourne while she was away filming the X-Factor in London.
Kris, 32, has just bought a £1 million house in Australia with Dannii, 39, and apparently missed her so much that he decided to ask for her hand in marriage.
A source told the Daily Mail: “Spending time away from Dannii and Ethan made Kris see just how important they both are to him and he really wants to cement his family unit by getting married. They had an emotional phone call and Kris told her he really wants Dannii to be his wife and Dannii burst into tears of joy.”
The couple are said to be planning to wed in Dannii’s home city of Melbourne.