I went the other way. My mate is a Leeds season ticket holder and use to bring my son scarves and programmes back from his European tours with Leeds. On my son's fifth birthday, he wanted a Leeds shirt and a day watching Leeds at Elland Rd. I obliged him, I got him the Leeds kit, my mate bought us tickets for the game and we went off to Elland Rd. In the pub, they brought out a Leeds United birthday cake with candles for him to blow out. This fad lasted about three months until he realised who his proper team was after regular visits to Ayersom Park and bought a proper kit.
I've got tons of pictures of him in his Leeds kit that I use against him on a regular basis. Sometimes you have to be cruel to be kind.