Retired footballer David was upset by comments made in a Daily Mail article after Harper was photographed sucking a dummy - called a pacifier in the US - as he dined out with her and his son Brooklyn in Los Angeles.
An expert in the piece claimed Harper should not be sucking on a dummy at her age and was risking "speech or dental" issues.
Sharing a screenshot of the page via Instagram, dad-of-four David hit back: "Why do people feel they have the right to criticise a parent about their own children without having any facts??
"Everybody who has children knows that when they aren't feeling well or have a fever you do what comforts them best and most of the time it's a pacifier so those who criticise think twice about what you say about other people's children because actually you have no right to criticise me as a parent."
David's post has already been liked more than 500,000 times and it's received more than 18,000 comments.
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