To each of us who has enjoyed a piece of birthday cake, the strains of "Happy Birthday to You" are as familiar to our ears as our own names. Yet how many people know the origin of the tune and its place in American history? In 1889 Patty and Mildred Hill, two Kentucky sisters, wrote the words and composed the melody of "Good Morning to All" for their kindergarten students. Initially written as a simple greeting and welcome, they later changed the...