Dancing With the Stars pro Derek Hough is sticking by his sister’s side after her Halloween costume faux pas.

Derek recently spoke out about the controversy surrounding Julianne Hough’s blackface Halloween costume and said that his sister is “mortified” about the criticism she’s received.

“She’s so apologetic,” Derek told E! News while backstage at last night’s Dancing With the Stars. “She’s so so sorry and I just hope that we can all forgive her and move on.”

The actress caused quite the stir when she went to a Halloween party on Friday night in Hollywood dressed as the character Crazy Eyes from the Netflix series Orange Is the New Black. Julianne put her hair up in knots, donned an orange jump suit with a prison tag, and went blackface.

Unsurprisingly, the controversial costume caused a public backlash. Julianne took to Twitter to apologize earlier this week, tweeting, “I am a huge fan of the show Orange Is the New Black, actress Uzo Aduba, and the character she has created. 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.”

Backing up his little sis, Derek says he hopes the public can forgive Julianne’s mistake.

“She’s my little baby sister and she’s the sweetest thing ever,” he said. “She is just beyond beside herself. Obviously, it wasn’t her brightest moment in her life, but hopefully we can move on.”

SourceE! News