You can hire Sophie in the Le Gordon Blue restaurant store.
Sophie may be required to help complete some level goals!
In the screen shot below Sophie must be used on 4 Maddie parties, as represented by the icon next to Maddie's head.
Once Sophie is used on a group of customers waiting in line, she will need two drink refills before she can be used again. It will take some time for Sophie to finish her drink, so time seating and serving your parties and taking care of Sophie!