<P> Cecilia Smith (2002--2004) (Ashlee Simpson) is Simon's girlfriend, who then dates Martin . She later dumps Martin, who loved her but she was not sure she felt the same . Another reason (which is not very clearly shown) might be that she thought Simon was returning--whereas he only came for vacations--and they might get back together (because it would no longer be a long - distance relationship). When Simon comes home (at the end of season eight), it was vaguely revealed that their relationship did not work out, because over the summer Cecilia went away to college, and it was only when Simon begins dating and having sex with Georgia (in season nine) that it is revealed that they had broken up . </P> <P> Cecilia becomes very close to the Camdens while dating Simon, and even when he leaves to go to college she still spends a lot of time with his family, babysitting the twins, helping out around the house and often being there for meals, this escalates when Annie is away looking after her sick father, she is there so often that Annie becomes jealous of her role in the family, with the twins loving her and saying she is "more fun than Mommy". Annie and Cecilia discuss this and Annie resolves her jealousy when she realizes Cecilia is just trying to help, and she continues to be part of the' extended Camden family' until she leaves for college . </P> <P> Martin Brewer (2003--2007) (Tyler Hoechlin) is the only son of the Marine, Bill Brewer . His mother died when he was young and, until he was 16, he lived with his Aunt Betsy, when his dad was deployed . During his sophomore year in high school, the Brewers moved to Glenoak . </P> <P> Martin walks into the Camdens' life by chance and joins the already - growing over-glut of teen boys there . He follows Ruthie and her then - boyfriend Peter to the Camden house and everyone assumes that he is a friend of Simon's, except Simon thinks that he is there to see his dad . While Martin's aunt, an aspiring fashion designer, wants the two of them to move to New York, Eric manages to convince her to let Martin stay with them so as not to uproot him again . </P>

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