Are they identical?

I often get a series of 3 questions, and it's most often in this order:

1) oh how cute!! are they twins? (yes, yes, they are - what else would they be?!)

2) is it a boy and a girl? (congrats, yes, you figured out the pink and blue theme!)

3) are they identical? (to which I normally just say no and leave it at that)

Today I had a follow up to the typical 3. The teenager started with the normal 3, but after the "no, they're not identical" he added "how do you tell them apart, how do you know which is the boy and which is the girl?". I don't think he was joking - I wasn't sure how to answer so I didn't. I was still chuckling over that one when I had someone else tell me that the twins look exactly alike, and am I positive they're not identical? Keep in mind this individual knows that Genevieve and Jackson are different genders...

People. You have to love them. :-)