"Feed the Birds" was a beautiful song in the musical/movie Mary Poppins, a famous 1964 Disney film. It is about a poor old lady who spends her time trying to feed the poor birds near a cathedral. Meanwhile next door, there is a bank full of people who couldn't care less.
Not made up by Nathan Fillion. Firefly was still a good show though.
But Mary Poppins is beautiful in a way unsurpassed.