Rude coworker

I made the mistake of telling a small group of co workers that my husband and I would be naming our son Hunter (they’d find out soon enough anyways), and one of them literally turned to another one, laughed and made a shooting gesture with his hand and said “really??”. I was pretty hurt that he’d make fun of my babies right in front of me. Granted, he’s Peruvian and maybe doesn’t realize it’s a relatively common American name? I left work feeling pretty bad about our choice and wonder how many other people will think the same thing? How did you handle people’s rude reactions to your babies name?