Bridge, who gave birth to her second son Carter on 15 August, said she knew Beckham would get stick for the photo as soon as she saw it.
"If I ever put a picture of Parker up on Instagram with him using a dummy, there's always someone who comments on the fact he has one," the mum-of-two wrote in her OK! column.
She added: "David said no one has the right to criticise him as a parent and I think he's right. It's their fourth child, so they know what they're doing."
The mum-of-two's opinion echoed the thoughts of many other parents who spoke out after the Daily Mail published an article claiming that using a dummy could have a detrimental effect on Harper.
Siobhan Freegard, founder of video parenting network Channel Mum told HuffPost UK Parents: "Every child is different, and every child’s reason for using a dummy is different. If Harper wants to hang onto her dummy for a short while after toddlerhood, where’s the harm?"
She said: "David is absolutely right to defend his parenting. It's no one else's place to comment. People are far too quick to judge parents, who are usually just trying to do their best. We know our children: strangers do not."