"At The Christmas Play" joke

The choir director selected the 6-year-old little boy with the
sweetest face for the opening scene of the Christmas play. "Now,
all you have to do, when you hear me say to the choir' ... and
the angel lit the candle', is come on stage and light all the
candles."
"I can do it, I can do it!" the little boy said, excitedly.
Rehearsals came and went, and finally the big night arrived. The
choir was ready, the stage was beautifully decorated with dozens
of unlit candles all around, and all awaited the moment when the
cute littlest angel would make his entrance.
The director gave the downbeat, the orchestra began to play, and
the choir swept into the introductory lines, ending with an
expectant "... and the angel lit the candle"
Everyone looked stage right for the entrance.
No little boy.
The director gave the downbeat again, and more loudly said,
"... and the angel lit the candle"
Again, all eyes looked stage right.
No little boy.
The director, beginning to sweat, motioned with great, sweeping
gestures, and this time the choir thundered into the line. So
loud were they that the curtains belled slightly from the sound!
"... AND THE ANGEL LIT THE CANDLE!"
And into the silence which followed came a clear, boy-soprano
voice floating piercingly from stage right "... and the cat peed on
the matches!"