The model and Myer Ambassador explained his and Dannii's decision to maintain their son's privacy in 2019, when one follower commented on a photo of Kris and Sarah's family, asking about Ethan.
"Where is your son? We never see him," the comment read.
Seemingly taken aback by the question, Kris responded: "And you never will on here."
In another response, Kris added: "This is a personal page where I post what I like, not what you 'think' you can demand."
Sarah jumped to his defence too, replying: "You see what we choose to share on our public pages. It’s not an open forum. Some of the most precious moments we share as a family you will never see."
Kris's fans also defended the star, branding the follower's inquisitive comment as "rude".
One fan commented: "Mind your own business."
"He doesn’t need to tell you anything, just appreciate what he does share," another wrote.
"There's NO need to be so damn bloody rude," someone else said.
Meanwhile, Kris and Sarah, are enjoying life with their two little girls at home in Melbourne.
As well as his Myer and Nissan ambassador duties, Kris is the co-owner of fitness business Fitstop and a self-tanning brand.
Sarah is a personal trainer who also runs her own prenatal and postpartum exercise program called BUMPFIT.
Kris and Dannii first met in Ibiza and began dating in 2008. Two years later the songstress gave birth to the couple's son in 2010.
The announced their split in 2012 via Twitter, after four years together.
"It brings me great sadness to tell you that Kris & I have separated," Dannii tweeted at the time.
"We still care for each other & ask for privacy at this difficult time, in particular for our son Ethan who remains our number one priority."
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