Questioning Her Mental Capacity

One of my students is now at university, and was telling me about another girl in one of her lectures. 

Girl: ... And she, just, like, constructed a fort from tables and chairs.  For no apparent reason.
Me: Why?
Girl: No idea.
Me: ... Does she do architecture? [no] Engineering? [no] So... why?
Girl: I have no idea.  But, we think she might have some... mental problems... I mean, she likes One Direction and Justin Bieber so I do question her mental capactity.

Gold.

Concerts

11-yr-old girl, in the middle of playing something, stopped and asked, rather urgently:

Girl: Oh!  Did you go to the Coldplay concert?
Me: Um...No... Did you?
Girl [dejected]: No...  So now I have to wait another 3 years for the next one. 
Me: Ah, yeah... that's really ... sad...
Girl [energetic again]: Ooh, One Direction?
Me: Ah, no.  You?
Girl [shaking head]: No.
Me: Is this a sad shake of your head?
Girl [surprised]: Yes!
Me: Um... Okay... That's... sad... for you... I guess.

She shook her head in a "You've just got no idea but I'm an 11-yr-old girl so you should listen to me" way, and kept playing from where she'd left off before.