Lily tries to comfort Barney who is enraged at the idea of Ted and Robin sleeping together again. Lily tries to get Barney to admit he still has feelings for Robin.
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In this clip from the the upcoming episode of How I Met Your Mother, Robin and Ted are driving each other nuts as roommates. They think maybe have sex will solve the problem... much like Barney thinks it will solve world peace.
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A preview clip of Speidi (Spencer Pratt and Heidi Montag) appearing on How I Met Your Mother on the magazine cover of "Them Weekly" that Marshall takes home to read while in the bathroom.
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Kim Kardashian appears on How I Met Your Mother as the cover girl on "Them Weekly" that comes to life and gives Marshall advice. Very funny!
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How I Met Your Mother Season 4 Episode 12 Quotes

You're right, super hot lady that my wife keeps telling me why you're famous but I keep forgetting

Marshall [to Kim Kardashian]

Barney: So I explained to her, I said Madelin, every single international conflict essentially boils down to sexual tension
Ted: Every international conflict?
Barney: Every single one, dude
Ted: So the crisis in the middle east could be solved by?
Barney: Gaza Strippers. Next.
Ted: Apartheid?
Barney: Apart Thighs? What else you got?
Ted: Cold war.
Barney: Ms. Gorbachev, Take Down Those Pants