Dancing With the Stars fan favorite Derek Hough's injuries are apparently very "serious," according to his sister, Julianne Hough.

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Derek had an incident on Monday in which he broke a toe and sprained his ankle, casting the rest of the season in doubt for the pro dancer. He is currently in recovery in Los Angeles.

Julianne spoke with E! News this week to update fans on his recovery, saying that things aren't exactly looking good.

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"It is serious," Julianne said. "I know that he broke his toe on his right foot and sprained his ankle in two different places on his left foot trying to get ice for the toe."

As for his overall spirits, he obviously still wants to be on the show regardless.

"He's super-bummed out because he's super-passionate about what he does and he wants to be there for his partner," Julianne said.

Derek said in a new Instagram post that the incident wasn't even in regard to dancing itself. He said that, "a fluke accident happened that involved a light and some stairs. Can't believe it, wish I had a cooler story to tell."

However, he said that ultimately he is "determined to come back" and be there for his partner, Nastia Liukin.

In the mean time, Liukin is rehearsing with pro dancer Sasha Farber. It is currently unknown if Hough will be able to return at any point this season or if he will be sidelined for the the final weeks of the competition.

Dancing With the Stars airs Mondays at 8 p.m. ET/PT on ABC.

Watch Liukin and Hough's latest dance here: