Gossip Girl co-stars Blake Lively and Penn Badgley, both 23, have called it quits after three years of dating, according to Us Weekly.

The couple broke up in mid-September, but kept news of the split under wraps for weeks. "Nobody on set had any idea," said a source close to the pair. "They're really just private."

But the separation hasn't affected the Gossip Girl set, which is currently filming its fourth season. "They’re professionals," the source said. "They're still good friends and hang out on the set."

The actors began dating in 2007, and met as preteens in L.A. –ISHITA SINGH

Read more about: