 In the days before Sarah s 21st birthday, the word "difficult" defines Sarah s new charge as an au pair to Ashley, and her rebellious teenage daughter Flynn, as well as dealing with Spence himself, who s still angry at Sarah since their failed time out, as well as his new girlfriend, a not-so-bright model named Leya. Meanwhile, Andy Beam, the smitten orthodontist whom Cecilia met during the Sarah and Romy s party months earlier, hires her as his new receptionist where she s liked by him, but not the patients. Also, Maguire and J.B. decide to go into the party-DJ business which turns into a competition for both of them when they both fall for Sophie, their party coordinator.