A kid near my house was being excessively naughty. So his mom asked him "how old are you?" to remind him to be a bit sober. He had answered that question many

A kid near my house was being excessively naughty. So his mom asked him "how old are you?" to remind him to be a bit sober. He had answered that question many times before, so this time he answered it a bit differently: "I am birthday number old". Mom says: "Huh? That doesn't make sense. What did you mean?" He says: "I mean, I am as old as the number of birthdays I have celebrated".