Barbara Joan Streisand was born on April 24, 1942, in Brooklyn, New York, the daughter of Diana (born Ida Rosen) and Emanuel Streisand. Her mother had been a soprano singer in her youth and considered a career in music, but later became a school secretary. Her father was a high school teacher at the same school, where they first met. Streisand's family was Jewish; her paternal grandparents emigrated from Galicia (Poland–Ukraine) and her maternal grandparents from the Russian Empire, where her grandfather had been a cantor.
Her father earned a master's degree from City College of New York in 1928 and was considered athletic and handsome. He married Ida in 1930, two years after graduating, and became a highly respected educator with a focus on helping underprivileged and delinquent youth.
In August 1943, a few months after Streisand's first birthday, her father died suddenly at age 34 from complications from an epileptic seizure, possibly the result of a head injury years earlier. The family fell into near-poverty, with her mother working as a low-paid bookkeeper.
She has an older brother, Sheldon, and a half-sister, the singer Roslyn Kind, from her mother's remarriage to Louis Kind in 1949. Roslyn is nine years younger than Streisand.