Story highlights Jackie Evancho says she's disappointed in the Trump administration's transgender policy

The singer's sister came out as transgender in 2015

(CNN) She sang the national anthem at his inauguration, but on Wednesday, Jackie Evancho spoke against President Donald Trump's politics.

".@realDonaldTrump u gave me the honor 2 sing at your inauguration. Pls give me & my sis the honor 2 meet with u 2 talk #transgender rghts ❤" she tweeted, minutes after the Department of Justice withdrew Obama-era guidance on transgender bathroom use in public schools.

. @realDonaldTrump u gave me the honor 2 sing at your inauguration. Pls give me & my sis the honor 2 meet with u 2 talk #transgender rghts ❤ — jackie evancho (@jackieevancho) February 23, 2017

The "America's Got Talent" star's older sister, Juliet, came out as transgender in 2015.

"She told me she was transgender, and I was actually very happy for her because she finally found herself, and she can be who she wants to be," Jackie Evancho told People Magazine at the time.

The singer wrote earlier Wednesday that she was "obviously disappointed" by the forthcoming decision.

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