What is the main conflict in The Trumpet of the Swan by E. B. White?

There are moral lessons to be learned all through the book. The main character in the book is the swan, Louis. Louis was born without a voice. A swan needs a voice in order to find his mate. Swans mate for a lifetime, so it is important to be able to court a lady swan by trumpeting to her. White calls the swan defective. Today we would say disabled. Louis overcomes his disability and wins his lady before the story ends.