Candace Cameron Bure, Taylor Neff and Heather O'Rourke all auditioned for the role of Vicki.
Vicki the Robot:
We don't have skeleton's in our closet... they're in the back of the condo.
Despite being "made of plastic, microchips here and there", the robot and her costume grew from season to season to accommodate the actress. However, in the season 4 episode "School Monitor", there was an explanation given by the father, who put in a special chip that enabled her to grow to avoid suspicion from friends and neighbors why she never grew and remained the same age.