Talk about awkward!
[Image via WENN.]
However, months went by without any mention of the photogenic twosome.
Well according to sources, the Almost Famous thespian and the dancer are not only back on… they've been secretly getting hot and heavy for a while!
On May 26, the couple were joined by sister Julianne Hough and her boyfriend Brook Laich at the U2 concert at The Forum in Inglewood, CA.
An eyewitness said:
What a grand finale!
And if that wasn't enough, Sia was there live singing her hit song Elastic Heart to give the soundtrack to the duo's performance (above).
Sia, of course, appeared with her face covered as she's been known to want to keep her privacy, but it didn't take away from the AH-Mazing performance she gave!
As per usual, Julianne and Derek were both absolutely incredible and we wouldn't expect anything less! The Houghs had a little help from mini versions of themselves that they paralleled on stage next to them.
Sia's song was a hauntingly beautiful soundtrack to each pair's struggles they showed through their interpretive dance.
Ch-ch-check out the amazing performance for yourself (above)!
She sashayed her way on the dance floor and now she's going to do it down the aisle!
On Thursday, Dancing With The Stars alum Amy Purdy announced that she got engaged to boyfriend Daniel Gale!
The double amputee snowboarder posted the following message on Twitter letting her many followers know that she's a taken woman!
Awww so cute!
She even added the (above) pic of the lovebirds on the beach!
But where exactly is her wedding ring?!
Pretty sneaky, sis!
The sibling rivalry came to a head when in order to take down Derek's hot take on Macklemore's Can't Hold Us, she totally pulled out a secret weapon — the real Meghan Trainor came out to help her sync All About That Bass!
But then things really heat up when Derek plays both Sia AND Maddie Ziegler with an interpretive Chandelier dance while Julianne Just Had Sex onstage!
See all the amazing sibling
singing syncing (below)!
The elder Hough sibling is about to go head-to-head against his sister Julianne on Thursday night's new episode of Lip Sync Battle, and we're getting a little treat of what's about to come.
We already saw Julianne perform I Just Had Sex on the hit Spike game show, but now it's Derek's turn.
And what else would a white male dancer lip sync to? Why, a white male rapper of course!
Ch-ch-check out Derek battle his sister with Macklemore's Can't Hold Us (below)!!!