Victoria Beckham's photo prompts question: Is it OK to kiss your child on the lips?

A photo posted on former Spice Girl Victoria Beckham's Instagram shows her kissing her daughter, Harper, while the two are swimming in a pool.

>> Read more trending stories  

"Happy birthday, baby girl. We all love you so much," Beckham wrote in the photo's caption, tagging her husband, David Beckham, and her son, Brooklyn Beckham.

The photo has racked up nearly 570,000 likes on the social media platform.

But many of the 5,200 comments on the photo say Beckham should not be kissing her 5-year-old daughter on the lips.

Happy Birthday baby girl We all love you so much  X @davidbeckham @brooklynbeckham kisses from mummy X

A photo posted by Victoria Beckham (@victoriabeckham) on

Comments like "That's gross," "That looks wrong" and "It looks like they're making out" criticized the photo and Beckham's actions.

"Normally with a member of your family you don't kiss on the lips unless it's your husband," said Liz Brewer, a British social etiquette coach. "With children, I wouldn't have thought it's a particularly good habit to get into but it's her child and she's at liberty to do what she thinks is best. I would be uncomfortable doing that, and I think most people would be. If she feels it's appropriate, so be it."

But many more people came to Beckham's defense. Some talked about their own affection that toward their children and the affectionate actions their own parents had shown toward them.

"What is wrong with people? It is a sign of affection and even if (some people) do not understand, always remember there (are) different kinds (of) culture and that she is a mom," one internet user wrote.

"My mum still kisses me on the lips and she's 61 and I'm 27! My Nan even used to kiss me goodbye all the time, I have so many fond memories and felt loved and safe with them," another said.

"I'll kiss on the lips and hug my children until a time that they don't want me to," one mother said.

Others called the photo a "beautiful" illustration of "true nurture and maternal instinct."