Peter finds out his father-in-law, Carter, is having an affair.
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!!Tropes:
* {{Blackmail}}: Peter threatens to tell Babs about how Carter cheated on her, unless Carter gives in to Peter's demands. Peter ends up blurting it out anyway.
* {{Hypocrite}}: Glenn Quagmire once again shows off his hypocrisy in this episode when he argues that marriage is a sacred bond and that those who decide to cheat on their significant others bring nothing but shame. This is coming from the man who slept with Cleveland’s wife, Loretta in a previous episode, and has gotten out of unwanted marriages through questionable methods both [[Recap/FamilyGuyS4E21ITakeTheeQuagmire before]] and [[Recap/FamilyGuyS11E11TheGiggityWife after]] this episode. Strangely enough, nobody calls Quagmire out for this.
* IndubitablyUninterestingIndividual: Babs' ex-boyfriend, Roginald could give Mr. Killington esquire a run for his money. He politely asks Babs if he could one day sit beside her in the same context that most people would suggest having sex, calling him a "rascal" makes him recoil in horror at "such language in the presence of a lady", and saying the word "penis" causes him to FaintInShock.
* KarmaHoudini: Peter does not receive any comeuppance for blackmailing Carter over his affair in the episode.
* LaserGuidedKarma: This episode is one for Carter as Peter decides to blackmail him to do many humiliating things in exchange for not telling anyone about his infidelity as revenge for all the crappy things Carter did to him over the years.
* MustMakeAmends: Since Peter feels bad about breaking up Babs and Carter, he sincerely tries to help Carter move on and then have the two reconcile.
* NotHelpingYourCase: When Peter catches Carter having an affair, Carter tries to make up an excuse, that results in Peter responding with “Ew!” The final "Ew!" is followed by [[EatTheCamera the camera zooming into Peter's mouth]].
-->'''Peter:''' Mr. Pewterschmdit, you’re having an affair, Ew!\\
'''Carter:''' No, No! This is my sister!\\
'''Peter:''' Ew!\\
'''Carter:''' No, No! I’m impotent!\\
'''Peter:''' Ew!\\
'''Carter:''' I mean, she looked at me while I did it to myself!\\
'''Peter:''' Ew!\\
'''Carter:''' I mean, she’s a man!\\
'''Peter:''' Eww!
* RunningGag: Peter takes out a boombox ''Film/SayAnything'' style and sings a ballad version of "Surfin' Bird".
* ShoutOut: Peter and Carter have a SeinfeldianConversation about The Big Bang Theory when Carter gives Peter one of his Hi-Def televisions.
* VerbalWeakness: Peter defeats Babs's ex-boyfriend Roginald with a single word.
-->'''Carter:''' Get away from my wife, you rascal!\\
'''Roginald:''' Such language in the presence of a lady! If it's a row you want, I will cleave you in twixt!\\
'''Peter:''' Hang on Carter, I think I know how to take this guy down. (to Roginald) Penis.\\
'''Roginald:''' Aaaaaaaah! ''[faints]''
* WhatYouAreInTheDark: Peter fails this singlehandedly. He finds out Carter is having an affair, and feels uncomfortable about keeping it a secret from Babs and Lois. His friends convince him to take advantage of the situation to blackmail Carter. Then Peter, after doing so, blabs about the affair in front of Babs, much to Carter's consternation.
* YouNoTakeCandle: The Pewterschmdits' Spanish maid and her son talk this way.
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