It sounds like Kristen Stewart's 21st birthday party turned into a double date!

Despite rumours that the Twilight twosome have split, Kristen Stewart and Robert Pattinson looked as lovey-dovey as ever while celebrating Kristen's birthday with co-star Taylor Lautner and his GF Lily Collins.

According to Celebuzz.com, the foursome were spotted goofing around at her birthday party, which also happened to be the official wrap-up party of the Twilight Saga: Breaking Dawn movie.

Sources revealed that Rob and Kristen "are affectionate, it's not like they try to hide their relationship anymore from their friends. They just aren't obnoxious about it and don't need to do it for the press."

A source also dished to UsMagazine.com that Rob "led the crowd singing for her, and you could tell she was so embarrassed but in a cute way."

Happy birthday Kristen! So does this mean they didn't break-up?!  We're so confused....