7 
1 -
1Quagmire went as far as interfering with Brians relationship with Ida - Brida -
2They plot to ruin the others life for no reason at all - Various episode including Brian The Closer -
3They did not show that feud in episodes before season 7 -
4Brian frequently tries to bond and spend time with Quagmire -
5A lot of the reasons Quagmire has for hating Brian are hypocritical -
6Their fighting has caused people to get hurt or killed -
7They fight with each other over very petty things - Various episodes
