Not long ago, G was watching a DVD that had a preview for an Arthur special called Arthur's Missing Pal. There's a moment in the preview (at 0:15, if you must know) where Arthur flings open the door of his house and dramatically shouts a single word to the neighborhood at large, and because I wasn't paying very close attention, I thought what he had screamed was "BLAAAAAAAAH!"
I said to G, "Why is he screaming 'BLAAAAAAAAH'?" and she said, through tears of laughter, "He's not screaming 'BLAAAAAAAAH,' he's screaming his dog's name, Pal. You know, 'PAAAAAAAAL!'"
We both laughed until we were nearly sick, and ever since then, we've been turning to each other at random moments -- in the grocery store, in the car, when I'm tucking her into bed at night -- and saying "BLAAAAAAAAH!" I'm sure this doesn't sound even slightly funny to anyone who wasn't there, but I've had to stop twice to stifle giggles while typing out the story.
It's the little things.