Brooks Laich and Katrín Tanja Davíðsdóttir are already marking their calendars for future playdates between their daughter and Derek Hough and Hayley Erbert's baby. Laich, 42, and pregnant fiancée Davíðsdóttir, 32, celebrated the news that Hough, 40, and Erbert, 30, are expecting their first baby on Tuesday, July 22. "LETS GOOOOOOOOO!!!!" Laich, who was married to Derek's sister, Julianne Hough, from 2017 to 2022, commented on the couple's announcement video on Instagram, adding a dozen heart eye emojis.