Berniece Inez Gladys Baker (born July 30, 1919 in Venice, California) is the half-sister of Marilyn Monroe.
Their mother Gladys was married three times. By her first husband "Jap" Baker, she had Berniece and her brother Robert, both born in Los Angeles County, California. Berniece's father, kidnapped her and her brother after their mother, Gladys, divorced him. Berniece grew up in Kentucky, and married Paris Miracle on October 7, 1938; their only child, Mona Rae, was born on July 18, 1939.
Meanwhile, Gladys after a short time in Kentucky, returned to Los Angeles where she married a second time, and eventually gave birth to Marilyn Monroe.
Berniece did not know she had another sibling until she was 19 after receiving a letter from Gladys; they met for the first time in 1944. Berniece worked for many years at the University of Florida. Her and Mona Rae's book, My Sister Marilyn (1994), not only shed new light on their famous relation, but on the family's history of mental illness.