I wasn't aware of Althea living in Harlem until I read her biography. I looked in the 1930 census for an Althea Gibson living in Harlem and found none. I then tried looking just for a Gibson (thinking that Althea may have been spelled incorrectly) who was three years old and originally born in South Carolina. Bingo! I found an Altha Gibson, age 3, born in South Carolina, living at 302 West 146th Street. She was living with an aunt named Sallie Dwyer and their rent was $65 (which seems pretty high by 1930 standards).