There may be a happily ever after for two stars of Once Upon a Time.
Following in the footsteps of Ginnifer Goodwin and Josh Dallas – whose relationship became public in April – fellow costars Jennifer Morrison, 33, and Sebastian Stan, 28, are an item, too.
“They met on set and are now exclusive,” a source tells PEOPLE. “They started dating three months ago. They seem to be really happy together, but are trying to take things slow.”