"Jo, I really have no words that could describe how I’m feeling 😢, but THANK YOU for sharing your love, support, spirit, kindness and smile with me and so many of us over the years," Anthony began his touching tribute alongside an old photo of the pair beaming at the camera.
Anthony continued: "You were there from the very beginning, at concerts, and other appearances over the last 15 years, you were and will always be part of the Anthony Callea fabric.
"You were adored by many, including me."
It is yet to be known how Jo passed away.
Our thoughts are with Anthony and Jo's family and friends.