'Dancing With the Stars’ Premiere: 5 Things You Didn’t Know About Rumer Willis

— -- intro: “Dancing With the Stars” kicks off its 20th season tonight, and the new cast for ABC’s dancing competition show is bound to bring some show-stopping moves.

The amateurs this season include an array of contestants from Michael Sam, the ground-breaking football star who became the NFL’s first openly gay player, to Charlotte McKinney, the buxom blonde bombshell best known for starring in this year’s hottest Super Bowl ad, to the newly engaged, farmer-turned-“The Bachelor,” Chris Soules.

But one contestant will have Hollywood A-listers supporting her -- because they are her parents.

Rumer Willis, who appeared on the ABC Family series, “Pretty Little Liars,” is the oldest daughter of Bruce Willis and Demi Moore. “Nightline” went behind the scenes with her and her dance partner, Val Chmerkovskiy, as they prepared for tonight’s big premiere, which airs tonight at 8 p.m. on ABC.

Here are a few things you might not have known about Rumer Willis.

quicklist:1title:Her Famous Family Will Be Cheering Her Ontext:Expect to see her star-studded family in the cheering section during tonight’s premiere.

“I feel really grateful that I have a family that’s so supportive of all the crazy and whacky things that I decide to do," Willis said. "So I feel very lucky that all of them are coming to support me.”

quicklist:2title:Her Family Remains Very Closetext:Although the Bruce-Demi split in the late '90s was very high-profile, Rumer Willis said her mom and dad continued to parent together, even after the divorce.

“They really set a trend of people who had split up being able to still really have a family dynamic,” she said. “I have so much gratitude that that’s the way I was raised, that I didn’t have to split holidays or birthdays. That they made such an effort to really still keep a family unit even if we had various families spread out everywhere.”

quicklist:3title:Training for ‘Dancing With the Stars’ Helps Her Stand Tallertext:When she started practicing for her “Dancing With the Stars” debut, Rumer said she gradually noticed a change in her body language.

“I noticed right away even just my confidence kind of when I would walk in to a room," she said. "If your life is always for public view... I didn’t realize it as much before, how much you kind of try-- or at least I have kind of tried to hide and I almost do that with my body language.”

“I think the worst mistake that you can make if you’re in the public eye is to try and hide and be not yourself," Willis continued. "Because I think truth and who you are will always be revealed. You can’t ever really hide who you are because eventually things tend to come out that way.”

quicklist:4title:Performing Live is Rumor’s New Jamtext:Although she has done television, Rumer said she found a new thrill in performing live. She made her musical debute in 2013 in the stage play, “For the Record: Baz Luhrmann.”

“It’s just fun,” she said. “I think it’s the same thing with dancing or anything live, that when you get the audience’s energy I think it really starts to kind of fuel what you’re doing, and when you see people’s responses good or bad, it’s kind of a fun thing to be able to work off the energy of the crowd.”

quicklist:5title:The Thing Rumor’s Partner Val Chmerkovskiy Is Worried About This Season Is…text:"Her parents,” Chmerkovskiy said, laughing. “[Bruce Willis] is a tough guy.”

“All jokes aside,” he added. “For me every season it’s I don’t know why, but the family of my partner is really important. … I feel like the opportunity to make your parents proud is I know, for someone like Rumer who is really close to her family, I think it’s a great opportunity and I feel very responsible for that."