More recently, "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."
As for what drew the two together, says the source, "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."
At the time of their first becoming acquainted – the summer after Ledger's Oscar nomination for Brokeback Mountain – Ledger and Olsen were spotted together having lunch at the Chateau with a group of friends, and Ledger was described as being charmed by Olsen, who made him laugh as he would scarf down a big meal.
"Mary-Kate made him laugh a lot," an eyewitness recalled.
Both the New York Post and Daily News reported this week that Ledger, 28, and the Olsen twin, 21, were dating.
Linked By a Phone CallWhatever their relationship, the two were again linked when reports surfaced that she received two phone calls from masseuse Diana Wolozin, who arrived for an appointment at the actor's New York City apartment on Tuesday only to find him dead in his bedroom.
Wolozin, aware that Ledger and Olsen were friends, used the speed dial on Ledger's cell phone to call Olsen in California to ask for help, sources said. Olsen told the masseuse she would call her security people in New York to assist in the matter.
Things were far more carefree back in the summer of '06, "They were all talking about scripts and telling funny stories about directors and people in the biz," remembers the eyewitness. They also shared something else in common: Both smoked Marlboro Reds.
By STEPHEN M. SILVERMAN, TIFFANY MCGEE, DAVID CAPLAN, ALYSSA SHELASKY
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