 The producers struggled to cast Jessie Bannon . Peter Lawrence ultimately chose Jesse Douglas , whom he felt reflected Jessie 's energy and intelligence — " [ Jesse Douglas ] has immense energy , huge energy , and is the kind of woman who could do all the kind of things Jessie could do — you know , athletic , smart , so and so forth [ sic ] . " Douglas impressed Lawrence with her active lifestyle , including ballet , equestrianism , and tennis . When asked about the character 's inclusion , Douglas stated , " I 'd be bummed if I upset anybody . Jessie is pretty cool . It is not like she is a girl who is whining all the time . If anything , she is a really good springboard for the rest of the storyline . " Roth supported her , claiming that " Jonny hasn 't discovered girls yet but when he does Jessie would be the type of girl he 'd like to be with ... I think something will happen between them but right now Jess is his best friend . " H @-@ B Chief Fred Seibert agreed , hinting that as adults " there might be a Tracy / Hepburn thing going on . " Turner approached George Segal to audition for the part of Dr. Quest . Segal described the show as having " a real family feeling about it ... I 'd never seen this stuff before . That was quite remarkable . " 
