The Home And Away actor, 41, and Marais, 31, were feeling the festive spirit with daughter Scout, 4. James captioned the image, "hoping everyone has a safe and joyful giving season."
In the past Stewart has addressed his 2015 split from Marais, admitting their almost ten-year age gap may have contributed to the marriage breakdown.
"Our relationship didn't work out because I think hearts go in different directions eventually," he told Sunday Life.