Sally is the daughter of Stan Sitwell, owner of a rival company to the Bluth family. Michael and Sally have known each other since they were teenagers and would've dated, but Michael's father George kept using their attraction to each other to aggravate Stan. Not wanting to incur the wrath of Stan, Michael kept his distance around Sally, eventually drifting away from her.
Years later, Sally and Michael meet up. Michael has lunch with Sally and Stan, but is embarrassed by his brother G.O.B. who is also on a date and decides to sit with them. Sally then mentions volunteering for a charity auction as a date. G.O.B. forces Michael to help him destroy Stan Sitwell's car so that he can offer his own car in exchange for a date with Sally. Stan gives Michael the money to buy Sally at the auction, but once Sally finds out she tells Michale she can't be attracted to a man her father approves of.
The next day, Michael recieves a gift-basket full of dating luxuries. Among them is two gift certificates for a private spa. Michael intends to surprise Sally by showing up at her office, but the receptionist tells Michael that Sally's out, even though he can see a blonde person in the office (actually Stan wearing a blonde wig).
Michale and Sally eventually start dating, but when an old flame shows up heavily pregnant, Michale assumes the baby is his and reluctantly tells Sally that they can't be together when he has an illegitimate child. Sally feels that Michael is always going to find a reason to not be with her and they break up.