Actress and dancer Julianne Hough shocked fans this weekend, appearing in blackface as part of a Halloween costume. Now, Hough's big brother is coming to her defense. In an interview with E!, Derek Hough opened up about his sister's recent slip up.

According to the "Dancing With the Stars" pro, Julianne is "mortified" by the public outrage over her blackface costume.

"She's so apologetic," Derek revealed to E! News. "She's so so sorry and I just hope that we can all forgive her and move on."

Julianne Hough Apologizes for Donning Blackface

The 25-year-old actress attended the Casamigos Tequila Halloween party in Los Angeles Friday night, dressed as Suzanne "Crazy Eyes" Warren from the Netflix series "Orange is The New Black." Hough completed her prison ensemble by covering her skin with dark makeup and knotting her golden locks into "Crazy Eyes'" signature twists. In the wake of intense backlash, Derek insists Julianne never intended to cause any harm.

"She's my little baby sister and she's the sweetest thing ever," he said. "She is just beyond beside herself."

Shortly following the incident, Julianne issued a public apology via Twitter, echoing her brother's sentiments.

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"I am a huge fan of the show 'Orange is the New Black', actress Uzo Aduba, and the character she has created," she wrote. "It certainly was never my intention to be disrespectful or demeaning to anyone in any way. I realize my costume hurt and offended people and I truly apologize."

As for the elder Hough, he is hopeful that the public will be forgiving .

"Obviously, it wasn't her brightest moment in her life, but hopefully we can move on," he said.

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