have a 2-sided blanket and games at their house get annoying at times (Vegas Bowl near-comeback was at their house - so close!). But he's mostly complimentary of BYU.
During school he was part of a U tailgate with the family invited. Of course my sister was in blue, and she was in charge of dressing the kids. They had agreed to split the kids between blue and red. My sister dressed one kid in blue as appropriate, and bought a Houston Cougars shirt for the other one. It was red as agreed, but not for the Utes!
What's your (friendly) rivalry story?