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Video footage of Dannii, 39, and her child was shown on the X Factor spin-off show The Xtra Factor on Sunday.
Host Konnie Huq announced: "Dannii visited us in rehearsals today with a very special visitor who's getting into music from a very early age."
To cooing from the audience, the short film showing mum and baby was then screened. And fellow judge Cheryl was overheard exclaiming: "Oh my god, on my god, that’s too cute," while doting Dannii proudly smiled.
Little Ethan is Dannii's first baby. She welcomed him into the world with her partner, rugby ace-turned-model Kris Smith, on July 5.
This has been a particularly successful year for Ms Minogue. As well as starting a family and continuing her role on the X Factor, she has launched her own fashion label and fragrance, become an M&S model, and written an autobiography.
And Dannii's made it clear that the real icing on the cake would be seeing her final act Matt Cardle win this series of the show.
After finding out he had made it through to the finals, the gorgeous brunette and her protégée posted a video on Twitter (below), celebrating his place in the last round and encouraging fans to vote for the 27-year-old former painter.
Celebrity love stories: Dannii Minogue and Kris Smith