Sadie Kosmokos is one of the pre-made downtownies in The Sims 2: Nightlife. She can be made playable by befriending and asking her to move in, or by marrying her. Sadie's career is randomized at the start of the game, and she is mainly interested in Food and Culture.
Her name is randomized when Downtown is generated. The name "Sadie Kosmokos" is only referenced in the game files. Like most downtownies in The Sims 2, Sadie has a customized facial structure. She uses a customized version of the 13th Maxis face template in Create a Sim.