Short story about flag

A boy was walking by a flag the day before the 4th of July and the boy asked it how it was doing, but the flag just waved. Then on the next day, it was the 4th of July and there was a flag on a float (it was really a man dressed as a flag) and it kept saying "Happy 4th of July!" and the boy said...
"Oh, I guess he just had to save his voice!"