It appears that this habit is being passed down to a further generation. My two-year-old nephew doesn't actually say anything recognisable yet, but last week my sister-in-law took him to a coffee shop during one of the World Cup matches. My nephew was playing quietly and apparently paying no attention to the television screen which was showing the rugby in the background - until the referee blew his whistle. Instantly, my nephew was on his feet in front of the screen, pointing his finger at the referee and yelling something loud and incomprehensible.
Suddenly, my brother isn't looking forward with such enthusiasm to my nephew's first recognisable words!