Brittany Matthews doesn't play when it comes to Jackson Mahomes ... and just told his "ignorant" detractors to "shut up" when it comes to attacking her brother-in-law on social media.
The wife of Super Bowl champ Patrick Mahomes went off during a Q&A sesh with fans via Instagram on Sunday ... with one person asking "how do you feel about the comments about your [Brother-In-Law]?"
The fan didn't single out any specific comments ... but Jackson's become a star in his own right, and has made headlines for everything from his TikTok dances, throwing water on Ravens fans to an alleged assault.