At a Christmas party where our friends' family friends were there.  16 year old girl was there.  My fiance and I were 30 and 25 respectively.  She was wondering if we were being "allowed" to drink because it was a private party/holidays.  We just kinda blinked at her and told her our ages.  She had thought we weren't even 21 yet.  Looking around at the lard barges who represented the adults in her social circle, I guess she conflated how fat you are with age.  Perhaps she doesn't know that she doesn't have to get fat when she gets out of highschool.