Even though Donny Osmond did well -- finishing second in combined judges' scores on last Monday's "Dancing with the Stars"' men's competition -- he says his sister Marie is keeping the sibling rivalry going!
"After it was all over, Marie turned to me, really excited about everything, and she said, 'I'm still a better dancer than you,'" Donny tells ET, who is exclusively with him at his Las Vegas rehearsal with partner Kym Johnson. He adds, "Thanks, Marie. I really appreciate that."
At 51 years old, Donny says his biggest competition is 21-year-old Aaron Carter and 30-year-old Joanna Krupa.
"Aaron has got energy for days, but I am going to dance like a teenager. I am. You watch," says Donny, who will be on the ballroom floor jive dancing tonight.
"There's so much energy in the jive and that is what we are going to bring across … just non-stop energy from beginning till end," he continues. "That is what the judges want to see. That is what I want the audience to see."
One thing that Kym and Donny won't be doing this week is theatrics, because judge Len Goodman criticized them for that aspect of their dance last week.
"We have three days to learn a new dance and this is what is going to happen, hopefully, until the finale if we are lucky enough to make it that far," Kym says. "We can't get lazy or look heavy in the legs, so I am going to be a drill sergeant."
Donny will have his own rooting section tonight with his wife Debbie, who viewers saw last Monday, and son Joshua, who will make his first appearance, in the audience.
"My little 11-year-old Joshua called me [last week] and said, 'Dad, you're cool,'" Donny says. "After the first dance, I had to go over there and kiss my wife. I had to do that because she's getting me through this whole thing, but Joshua is really looking forward to being there tonight."
"Dancing with the Stars" airs Mondays and Tuesdays on ABC.