Birdsong

Consider the birds.
All day long they're singing.
I wonder if they ever have a bad day?
Are they ever disappointed?  Discouraged?
Do they ever grow weary of their toil?        
Surely their life is not without hardship and pain,
Yet still I hear them singing their cheerful song.
Maybe they know something that I don't know.
Perhaps there's something to learn from the birds.