We are now getting a clearer idea of the relationship between the world-famous Olsen Twins and the mysterious death of actor Heath Ledger. Heath and Mary- Kate Olsen were engaged in a “Friends with Benefits” relationship for over three months, PEOPLE Magazine reports. “Mary-Kate made him laugh a lot.”

“Mary-Kate and Heath were casually dating for three months before Heath’s death,” a source has told PEOPLE. “They were hooking up, but neither were particularly interested in making it exclusive.”

“They had a bond that was based on partying, and they had the same tastes in partying … like, in terms of where they liked to hang out in New York, what time they would want to go out. They just had the same sensibility.”