The Little Stranger Fred overhears Wilma on the phone mentioning ""a little stranger"" who will shortly be visiting the household. Assuming that Wilma is pregnant, Fred summon his dreaded mother-in-law. But the ""little stranger"" turns out to be Arnold the paperboy. Details Casts Title The Little Stranger Genres Family Animation Comedy Kids Release Date 1962-11-02 Episode Runtime 00 Hours 25 Minutes Season Number 3 Episode Number 8 Production Companies Hanna-Barbera Productions, Screen Gems Television Alan Reed Fred Flintstone (voice) Mel Blanc Barney Rubble (voice) Jean Vander Pyl Wilma Flintstone (voice) Bea Benaderet Betty Rubble (voice)