|Series||Foster's Home for Imaginary Friends|
|Nano Item||Hair Clip|
|Voiced by||Grey Delisle|
Frances "Frankie" Foster is Madame Foster's 22-year-old granddaughter and the all-purpose caretaker at Foster's. She cooks, cleans, buys groceries, drives the transport bus and is basically in charge of tending to the physical and emotional needs of the house's many imaginary friends. A spunky and compassionate girl -- albeit sometimes overwhelmed by her job and certain troublemaking residents and the uptightness of Mr. Herriman -- she is friends with most of the imaginary friends at Foster's (particularly Wilt, Eduardo, Coco, Bloo and the eight-year-old boy Mac, and also Goo) and can be described as a protective big sister to them.
In FusionFall, she's found standing outside the Foster's Gate. She is worried about Coco running off and Mac going to find her. (This is a reference to the episode "Mondo Coco," in which Coco goes through various misadventures and comes into contact with various obstacles when somebody leaves the door to Foster's open, and at the end of the episode, Frankie yells, "Who left the door open!? Who knows what would happen to Coco if she got out?!") Nevertheless, she expects them to be at the KND Jungle Outpost. Nearby the house, Mandark has started a construction of an Imaginasium, so he can better study Imaginary Friends. Frankie has gotten into arguments with him about the designs. Eddy secretly has a crush on her, and only mentions it in one of the Imaginary Reinforcements mission parts. Frankie has given her hair clip to the KND and Urban Rangers' scientists for Nano development.