"At The Christmas Play" joke

{I heard this years ago - have no idea where it first came from}
The choir director selected the 6-year-old little boy with the sweetest
face for the opening scene of the play. "Now, all you have to do is,
when I direct the choir to sing '...and the angel lit the candle', you
come onstage and light all the candles."
"I can do it - I can do it!" the little boy said, excited to be the
one picked.
Rehearsals came and went, and finally the big night arrived. The choir was
in grand voice, the stage was beautifully decorated with dozens of unlit
candles all around, awaiting the moment when the cute littlest angel made
his interest.
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," and everyone looked stage right
for the entrance. No little boy. The director gave the downbeat
again, and gestured for a louder line, which the choir gave him -
"...and the angel lit the candle," and again, all eyes looked stage
right. No little boy.
The director, beginning to sweat, motioned with great, sweeping
gestures, and the choir thundered into the line - 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!"