EXCLUSIVE

NeNe Leakes' son, Brentt, was trying to help his mom out on her tour but got robbed by an irate fan instead.

Brentt was hawking mom's merch Wednesday night when her "So Nasty, So Rude" comedy tour rolled through The Promontory in Chicago. Our PD sources tell us a customer was demanding a refund, and when the 17-year-old didn't fork it over ... the guy made off with a backpack containing Brentt's wallet and laptop.

We're told cops already have surveillance of the heist, but haven't made any arrests yet. Brentt wasn't hurt, and we're told he and NeNe are actually more pissed about losing his ID.