The Dog in the Manger Lyrics

A Dog lay in a manger, and by his growling and snapping prevented the oxen from eating the hay which had been placed for them. 

"What a selfish Dog!" said one of them to his companions; "he cannot eat the hay himself, and yet refuses to allow those to eat who can." 

Moral : We should not deprive others of blessings because we cannot enjoy them ourselves.