'The Ugly Duckling'  is a literary fairy tale by Hans Christian Andersen. Andersen lavished great care on this story, spending a year perfecting it. It was first published in 1844. 
A mother duck hatches six pretty little ducklings. A seventh bird is hatched. He is homely. The other ducks abuse him. He runs away. He is given a home by an old woman. Her cat and hen do not like him. He runs away again. Winter comes and a kind farmer gives him a home. The little bird almost dies. Spring comes. The 'ugly duckling' has grown into a beautiful swan. The other swans welcome him as their own. They bow to him. He is happy for the first time in his life.
The moral of the tale: 'it does not matter if you were born in a duck yard if you have lain in a swan's egg.' 
Andersen considered the story 'a reflection of my own life.'