How did Charles become "Bill"?

When I was young, I asked my grandmother (Bill's mother) why people called my dad Bill when his name was Charles. When someone did call him Charles, the name sounded like someone else, not my dad.

My Grandmother did have an answer, as I suspected sho would. It seems that when Bill was born, his older brother, Walter, then three years old, liked the song "Billie Boy" and proceeded to greet his baby brother with a, "Hi, Billie Boy, how are you doin?" The novelty of that stuck and very soon Charles became Bill for all time. I must have been five years old before I knew that my dad was Charles and not Bill by legal name.

The Charles "Bill" or C. "Bill" came into use in the telephone directory as many people would hunt for my parents telephone number by looking under William Smith, which was certainly a dead end search.

Thus the mystery of the name "Bill" has been solved.