RIO DE JANEIRO (CBSNewYork/AP) — NBC announcer Al Trautwig said Monday he regrets tweeting that the adoptive mother and father of American gymnastics star Simone Biles were not her parents, a declaration that angered advocates for adoption.

Trautwig had been scolded by a woman on Twitter for not referring to Ron and Nellie Biles as the 19-year-old Olympic gymnast’s parents. Ron Biles, who is the gymnast’s maternal grandfather, and his wife, Nellie, adopted Simone and her sister, Adria, in 2000 after they spent time in foster care.

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NBC ordered Trautwig to delete his tweet.

“To set the record straight, Ron and Nellie are Simone’s parents,” Trautwig said Monday.

Simone Biles of the United States competes on the balance beam during women's qualification for artistic gymnastics at the Rio 2016 Olympic Games on Aug. 7, 2016. (Photo by Ezra Shaw/Getty Images)

Simone Biles of the United States competes on the balance beam during women’s qualification for artistic gymnastics at the Rio 2016 Olympic Games on Aug. 7, 2016. (Photo by Ezra Shaw/Getty Images)

Carrie Goldman, who lives outside of Chicago and writes a blog, “Portrait of an Adoption,” said NBC and its personnel should not minimize the role of adoptive parents. She said Trautwig should apologize to Biles; NBC had no comment on whether he would.

It’s the second public misstep in as many days for an NBC announcer, after swimming commentator Dan Hicks was ripped online for referring to the husband and coach of a Hungarian swimmer as “the guy responsible” for her strong performance. Trautwig’s case involved an athlete NBC expects to be one of the biggest stars of the Rio de Janeiro Games.

Simone Biles went to live with her grandparents in Texas while their mother struggled with drugs and alcohol in Ohio, and was adopted when the birth mother’s parental rights were terminated. Simone remains in contact with Shanon Biles but is quick to correct anyone who calls Shanon her mother. Shanon Biles is her biological mother, she says. Nellie Biles is mom.

“Mother” and “father” were also the phrases used by NBC in a profile of Biles that aired Sunday night.

Shortly thereafter, Trautwig said on the air that Simone “was raised by her grandfather and his wife and she calls them mom and dad.”

A woman on Twitter then urged Trautwig to stop calling Ron and Nellie her grandfather and his wife. “They are her parents,” she wrote. But Trautwig replied in his since-deleted tweet: “They may be mom and dad but they are NOT her parents.”

If she’s been adopted, they are her parents — legally as well as emotionally, advocates said.

“If they are parenting her — that’s what a parent does — don’t diminish the role by calling them something other than her parents,” said Chuck Johnson, president and CEO of the National Council for Adoption. “Some of us would find that offensive.”

Goldman said she hopes NBC uses the opportunity to educate viewers about adoption, given the Olympics’ big audience and Biles’ high profile. Trautwig’s statement was a good first step, she said.

“Clearly the tide of public opinion has gotten through to NBC,” she said.

Judging by some of his other tweets, Trautwig was in a cranky mood Sunday.

To one tweeter who complained about losing five years of his life every time Trautwig explained the gymnastics scoring system, the announcer replied: “Then you should be done by now.” To another who said that he’ll watch pingpong if he had to listen to Trautwig’s voice any longer, he replied: “Enjoy what is called table tennis.”

Someone with the Twitter handle “Gym Nerd” wrote to Trautwig that “you may be in Rio but at least I’m passionate about my job, and respected for it.”

“Right, and I don’t care,” Trautwig replied. “Resume treatment.”

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