AceShowbiz - %cChace Crawford% is reportedly dating his "Blood and Oil" co-star %cRebecca Rittenhouse%. The rumored couple was seen so close to each other during Chace's 30th birthday party at the London Hotel in West Hollywood, California, on Saturday, July 25.
"Rebecca was by Chace's side most of the night," a source tells Us Weekly of the rumored couple at Chace's birthday. "I wouldn't call them official," the source continues, "but there is a romance between them for sure."
The two have been frequently spotted hanging out together. "He and Rebecca have been hanging out," another source says, adding that although there is "nothing serious," "they had great chemistry on set and he really enjoys hanging out with her."
Chace's birthday party was also attended by some other celebrities including his "Gossip Girl" co-stars %cEd Westwick% and %cJessica Szohr%, as well as %cZelda Williams%, %cJC Chasez% and %cCaroline Wozniacki%.
"It was a very dressed up night and people were really laying into him," a partygoer talked about the party. "%cTony Romo% had the best jokes of the night, he and Chace are very close and have a great bond...Everybody had fun partying afterward as well," the partygoer added. "It was a big blowout."