Cassidy Phillips developed several relationships over the course of the series.


Cassidy and Kate
First Episode: "Left Behind"
Origin: Kate helped Cassidy pull off a con to avoid a police encounter.
Since Then: Cassidy helped Kate visit her mother. After the island, the two met regularly, their children playing together.
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Cassidy and Sawyer
First Episode: "The Long Con"
Origin: Con gone wrong
Since Then: Before the crash, Sawyer, a con man, has, by and large, deceived and used people to gain an advantage, usually women like Mary Jo and Jessica. He has used one particular con on several occasions that involved him seducing married or recently divorced women, then alluring them to 'invest' on a phantom deal using their husband's money or their alimony, which he would then swindle. During one such instance, he tried to pull this con on Cassidy, a recent divorcee, who caught on to his con fairly quickly. Instead of turning him in, she requested him to teach her how to con, and he obliged. Over time, he claimed to have developed feelings for Cassidy. Ultimately, however, Sawyer ended up pulling a long con on Cassidy, swindling both her and an associate he was working with on obtaining Cassidy's money. Cassidy reported Sawyer to the authorities, and he went to jail. After about a year after he conned her, she visited him in jail and told him that she gave birth to their daughter, Clementine. Sawyer denied vehemently to being the father, but he later opened up a bank account for Clementine from the money he acquired in a prison con on a fellow inmate.
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