Aw, those happy Houghs! Dancing With the Stars pro Derek Hough hosted a viewing party for Fox's Grease: Live production on Sunday, January 31, and posted several updates of himself praising his younger sister Julianne for her portrayal of Sandy. 


Derek, 30, first shared a clip of his sibling, 27, and Aaron Tveit (Danny Zuko) singing the unforgettable classic "Summer Nights." As the song ends with the two standouts harmonizing perfectly, Derek and his guests get rather rowdy and applaud in front of the television. "Yeah, girl!" the big brother yells. "Killin it!" In his video caption, he continued: "#GREASELIVE my Sister ! Proud as a mutha."

Killin it ! #GREASELIVE my Sister ! Proud as a mutha

A video posted by Derek Hough (@derekhough) on

The dance professional followed up with another Snapchat of himself reacting to the show. "I'm straight-up emotional right now," he says in the clip. "That was beautiful, Julianne! I'm so proud of you!"

Singing live for all to hear!!!! Nailed it! #emotional #proudbigbrother

A video posted by Derek Hough (@derekhough) on

"Singing live for all to hear!!!!" the DWTS mirrorball champ captioned the clip. "Nailed it! #emotional #proudbigbrother."

Just last month, the Dancing With the Stars judge told Us Weekly and other reporters at the Television Critics Association that she was excited about doing the show in one take.

"That live-audience element helps so much,"she said. "I always say that we can be in rehearsal or on stage and give 100 percent, but when there’s an audience, there’s this, like, reserve tank where … it’s this extra little oomph. That’s where magic happens, and that’s why I think we are so excited that we have the live-audience element."

And for those watching from home — like her brother? "That’s how we are creating it. It’s for television," she elaborated. "So when people — our families, our friends — are introducing their kids for the first time to Grease, they are going to feel really involved as well. They are going to be singing along and dancing, I hope."

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