(AP Photo/Rebecca Blackwell)

NBC gymnastics announcer Al Trautwig is under fire for his response on social media to a critic who took issue with how he categorized Simone Biles' adoptive parents.

The gymnast and her younger sister were adopted by their maternal grandfather, Ron Biles, and his wife, Nellie, after spending time in foster care. Simone Biles refers to them as her parents.

Trautwig, though, on air has refered to Nellie and Ron as Simone's grandparents.

When a woman tweeted to Trautwig that he should refer to Ron and Nellie as her parents, Trautwig tweeted back: "They may be mom and dad but they are NOT her parents."



  He was criticized by Carrie Goldman, an adoptive mother who writes a blog, "Portrait of an Adoption." Goldman said NBC needs to make sure their commentators are educated about adoption.