My youngest is 7 and has always been precocious. He has a great sense of humor and has been cracking jokes (consciously and unconsciously) since he was about 18 months old.
A couple of days ago he began bantering with Daddy. His final jab was: "Daddy you're so old...like 21 or something."
I about died laughing. Now I know I'm not 21 anymore but I certainly never considered that old!
So what age do you consider "old"?