"Too many moms have been shamed for breastfeeding," Tanja Krstic Radusinovic tells PEOPLE

Tanja Krstic Radusinovic was breastfeeding her 9-month-old son at a pool when she was approached by a man who asked her to stop, even though she was covered by a towel.

“He looks at me all serious and mumbles, ‘I don’t think you should be doing that here,’ ” Radusinovic, 35, recalls in a now-viral Facebook post.

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The Las Vegas-based mom-of-three was angered by his comments, but before she could react, the man’s mother came up to him and reprimanded him for her.

“I had no idea I raised you like that, Kevin!” the man’s mother said, according to Radusinovic’s post. “I am not talking to you until you apologize! I breastfed you until you were 18 f—ing months, Kevin! […] It is f—ing normal.”

Radusinovic says that Kevin did apologize for his remarks, though his mother continued to be angry about the situation.

“Too many moms have been shamed for breastfeeding,” Radusinovic tells PEOPLE of why she thinks her post went viral. “Most of my friends are breastfeeding moms, so I guess they saw themselves in it because they’ve had similar experiences – they’ve had people telling them to cover up or leave the area. Once I posted it, everyone just went nuts and kept sharing it all over Facebook and Instagram and everywhere.”

She hopes her post makes others think twice before shaming women who are breastfeeding in public.

“Leave moms alone!” says Radusinovic. “It’s normal. I can’t believe that grown-up men – and women – would be offended by a baby eating. If I were bottle feeding, that would never have happened.”