Jeff Vespa/Getty; George Pimentel/Getty
Kristen meets Katniss!
and Jennifer Lawrence
hung out during the Toronto Film Festival on Saturday, where the actresses were at the Hotel Intercontinental promoting On the Road
and Silver Linings Playbook
"After being introduced, Kristen and Jennifer were soon chatting like old pals," a source tells PEOPLE.
"They were so excited to meet each other," the source says. The duo was joined by Bradley Cooper
, Lawrence's costar in Silver Linings Playbook
Lawrence even invited Stewart to a party for Silver Linings Playbook
at the Soho House later that evening.