Barber was born in West Chester, Pennsylvania, the son of Marguerite McLeod (née Beatty) and Samuel Le Roy Barber. He was born into a comfortable, educated, social, and distinguished American family. His father was a physician; his mother was a pianist of English-Scottish-Irish descent whose family had lived in the United States since the time of the American Revolutionary War. His maternal aunt, Louise Homer, was a leading contralto at the Metropolitan Opera; his uncle, Sidney Homer, was a composer of American art songs. Louise Homer is known to have influenced Barber's interest in voice. Through his aunt, Barber was introduced to many great singers and songs. Sidney Homer mentored Barber for more than 25 years, and profoundly influenced his compositional aesthetics.