Simone Biles's younger sister adopted with her is Adria. Simone and Adria were formally adopted in 2003 by their maternal grandfather, Ron Biles, and his wife, Nellie Biles, after the sisters had spent time in foster care.
The adoption followed a period of family instability. Biles's birth mother, Shanon, struggled to care for her children, and the siblings moved in and out of foster care. Ron and Nellie first began caring for Simone and Adria in 2000, when the girls were still children, and later made the arrangement permanent.
Adria also became a gymnast, although Simone reached a much higher level internationally. The sisters grew up together in Spring, Texas, where Simone later trained and developed into an Olympic champion. A common mix-up is confusing Adria with Nellie, who is Simone's adoptive mother, or Shanon, her birth mother.