By Andrew Holleran Patrick Mahomes isn’t the only member of his family who’s been making headlines this NFL postseason. The Kansas City Chiefs quarterback’s fiancee, Brittany Matthews, made some controversial headlines of her own. Following the Chiefs’ epic win over the Bills, Mahomes’ fiancee was seen pouring champagne over the fans sitting below her. While many Chiefs fans had no problems with this move, others on social media were critical. Many disagreed with that sentiment, though. “Y’all nicpic everything they do the fans literally asked for her to do that and they didn’t gaf because the…