Derek Hough and Hayley Erbert Hough chat with ET’s Denny Directo at week 4’s Dedication night on ‘Dancing With the Stars,’ which airs on ABC and streams on Disney+. Hayley opens up about returning to the ballroom for the first time since her emergency brain surgery last December. Derek reflects on how big of a moment it was to see his wife back out there and to share her story in more depth. Plus, Derek dishes on getting to reunite with his pal and fellow former ‘DWTS’ dancing pro, Mark Ballas, but this time with both of them at the judges table.