In June, JK Rowling released an essay and a series of tweets calling for limits on transitionary care for trans youth.
Business Insider reports that Rowling also mocked gender-inclusive words.
Cynthia Nixon told the Independent JK Rowling's transphobic comments were "really painful" for her 23-year-old transgender son, Samuel.
"It was really painful for him because so much of his childhood was tied up with Harry Potter," Nixon said.
"We're a Harry Potter family."
The failed gubernatorial candidate said she and her son still watch the films because they have "found home" in the series.