updated 02/02/2011 AT 8:00 AM ET
•originally published 02/02/2011 AT 3:35 PM ET
It was hard to miss: Justin Timberlake and Mila Kunis spent much of the night after the Screen Actors Guild Awards hanging out together at the PEOPLE/Entertainment Industry Foundation SAG Gala.
Then later on Sunday night, the singer/actor and his Friends With Benefits costar were “pretty inseparable” at another bash thrown by the Weinstein Company and Dewars, an observer says.
But a source insists “they’re friends” – period.
As for Timberlake’s girlfriend, Jessica Biel, the actress rarely walks a red carpet with Timberlake. But despite their lack of PDA, “Justin and Jessica are definitely together,” says the source. “They’re happy in their relationship.”