In the episode ‘Convention’ Malcolm’s parents travel to a business convention and hire a babysitter to watch over Malcolm and his two brothers.
Patty Henderson (Melody Perkins), the babysitter turns out to have had a crush on Malcolm’s older brother at school. But when she speaks to him on the phone he blanks her, not realising how she’s changed and lost weight in the meantime.
It seems that having once been fat has almost the same effect on other people’s perception of you as having once been a Power Ranger has on our perception of an actress’s acting ability.
Matthew Mungle (W.M. Creations inc) was responsible for Melody’s transformation.