Other Kris fans were also quick to stand by the Myer model.
One wrote: "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," one said.
Kris and his ex-partner Dannii Minogue have a nine-year-old son together, Ethan, who they co-parent.
It is believed that Dannii has requested that he not be shown on social media so he can live a normal life, away from the spotlight. She does not share images of Ethan on her social media pages either.
Meanwhile, Kris and Sarah, who is seven months pregnant, are enjoying a babymoon as they get ready to welcome their second child together.
The gorgeous pair have not an inch to pinch, as Sarah, who specialises in BUMPFIT prenatal and postpartum exercise programs, shared a full-length bikini shot.
Kris captioned one shot: "Spending some much needed time reconnecting with my beautiful family."