Plunket is facing a barrage of criticism after installing a front-facing carseat for Prince George ahead of the Royal tour.
The non-for-profit recommends children under two-years-of-age use a rear-facing carseat, however, both options meet legal requirements.
Plunket's Facebook page has been inundated with negative feedback.
Jenny Sincock posted the organisation had undermined their own safety recommendations.
"Should never have turned fitting his seat into a publicity stunt because it's only going to undermine Plunket's safety recommendations and tarnish their reputation.
"If Kate & Will wanted it forward facing then fine, but Plunket should have had nothing to do with supporting that decision publicly like this."
However, the organisation says it's a parent's choice.
Baby On The Move's Juanita Murphy told ONE News rear-facing carseats should be part of the legislation.
"We would love to see the legislation support what the recommendations is which is to keep rear-facing until two years of age," said Ms Murphy.
The Royal Visit Office says the carseat and its direction were requested by Kensington Palace.
The Duke and Duchess of Cambridge and Prince George arrive in Wellington on Monday.