When I was about 3, my father took my mother out to dinner for her birthday. I was a fairly well-behaved 3-year-old (usually!) so they brought me along.
At the end of the meal, a few of the waiters came out with a piece of cake with a candle and sang "Happy Birthday". My dad and I joined in, the people at nearby tables applauded, you know the drill... Well, I stood up and announced "My mommy is ___ years old!!" More applause from the other restaurant guests, while my mother turned a lovely shade of crimson