NBC announcer slammed for comments about Simone Biles

United States' Simone Biles performs on the balance beam during the artistic gymnastics women's qualification at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Sunday, Aug. 7, 2016. (AP Photo/Julio Cortez) (Copyright 2016 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistribu)

An NBC gymnastics announcer has apologized after he came under fire on social media over comments he made about the adoptive parents of American gymnast Simone Biles.

Al Trautwig says he regrets tweeting that the adoptive mother and father of American gymnastics star Simone Biles were not her parents.

Trautwig had been scolded by a woman on Twitter Sunday for not referring to Ron and Nellie Biles as the 19-year-old gymnast's parents. Ron Biles, her maternal grandfather and his wife Nellie adopted Simone and her sister after they spent time in foster care.

NBC ordered Trautwig to delete his tweet that said Ron and Nellie Biles "may be mom and dad but they are NOT her parents."

The tweet angered advocates for adoption. Trautwig said on Monday, "to set the record straight, Ron and Nellie are Simone's parents."

Trautwig on air referred to Nellie and Ron as Simone's grandparents.

He was criticized by Carrie Goldman, an adoptive mother who writes a blog, "Portrait of an Adoption." Goldman said NBC needs to make sure its commentators are educated about adoption. She says the comments deeply disrespect adopted children and parents.

When she was a toddler, Simone and her little sister, Adria, still in diapers, went to live with their grandparents in Texas while their mother struggled with addition to alcohol and drugs back in Ohio.

The couple adopted Simone and Adria in 2000 when the birth mother's parental rights were terminated.

Ron and Nellie provided the structure that the girls needed and set the foundation that helped produce what could be the greatest gymnast of her generation.

Simone is the three-time reigning world champion who has won 14 medals at worlds, including 10 gold, since 2013, and is poised in Rio de Janeiro to become the fourth straight American to win the Olympic all-around gold.

Though Simone remains in contact with Shanon Biles, she is quick to correct anyone that calls Shanon her mother. Shanon Biles is her biological mother, she says; Nellie Biles is Mom.

The Associated Press contributed to this report.