08/21/2012 at 06:00 AM EDT
A handful of Dancing with the Stars
alums and pros acted like one big, happy family on Sunday night.
, Derek Hough, Chelsie Hightower and Ricki Lake joined Karina Smirnoff to support her former partner Gavin DeGraw at his concert at the Greek Theatre in Los Angeles.
"At @GavinDeGraw concert with the gang!" Smirnoff Tweeted
, along with a photo of the group. "Woo hoo!"
Following the show, the gang made their way to the Living Room Lounge at the W Hollywood for the hotel's popular Sunday Jazz Series
, where Kenny G, Kellan Lutz
, Ashley Greene
, Lucy Hale and fellow former DWTS
contestant Michael Bolton were all on hand as well.
"Julianne gave Gavin a lap dance," an onlooker tells PEOPLE. "It was in front of her brother and their whole DWTS
crowd!" – Michele Stueven