Robin: It's totally a thing. Her brain is marinating in a cocktail of hormones, mood swings and jacked-up nesting instincts. I mean, yes, right now Lily is a goddess bestowing the miracle of life, but damn, she dumb!
Marshall: Well, I have noticed some stuff.
[flashback to Lily and Marshall's apartment:]
Lily: I can't find my keys or wallet anywhere!
Marshall: I found them... here in the freezer. Hey, but where are the ice cube trays?
Lily: No idea. [picks up dripping-wet purse] Those poor ice cubes! [sobs]
[present:]
Marshall: I guess she has been a little off lately.
Robin: A little? She just texted me wanting directions back from the bathroom. [to Lily, who's at the bar] Oh. We're over here! You're doing great, sweetie!