FAMILY GUY Season 4 Episode 6 : Petarded
After winning a game of Trivial Pursuit, Peter is convinced he is a genius. To prove Peter wrong, Brian suggests he take a test of the MacArthur Genius Grant. The test results say that Peter is technically mentally challenged. Peter has no problem abusing this handicap until Lois is injured and the kids are taken away because Peter is not mentally fit for parenting.