Joe and Petunia are characters from a well known series of public information films in the UK. They appeared in four films which ran between 1968 and 1973, and they became popular so quickly that it was decided to kill them off in the final short Worn Tyres Kill in order to prevent public demand for their reappearance. They also appeared in a much earlier public information film which showed them learning to use a pelican crossing, but it is noticeably different from the others in the series.
The Joe and Petunia series was made by Nicholas Cartoons, also responsible for the 1978 television series Willo the Wisp. The films were animated and featured Joe, a tiny little man in pinstripes, and Petunia, his enormous wife who wore a hat and sunglasses and could often be seen licking an ice cream noisily. Voices were provided by Wendy Craig as Petunia, later replaced by Brigit Forsyth for the last film, and Peter Hawkins as Joe. In each film, they caused danger with their unbelievable stupidity, advising the public on what not to do in a similar situation.
The public information films these characters appeared in were:
The "Coastguard" film was shown on UK screens for a limited run from May 2006 to celebrate the 60th anniversary of the Central Office of Information. It was digitally remastered and "updated" to give it a more modern look - in the new film, Joe has a mobile phone, Petunia listens to an iPod and the coastguard now uses a computer.
This is, according to Harry Potter author, J.K. Rowling, where she got the name for Harry's Aunt Petunia. "Vernon and Petunia were so-called from their creation, and never went through a number of trial names, as so many other characters did," Rowling writes. "‘Petunia’ is the name that I always gave unpleasant female characters in games of make believe I played with my sister, Di, when we were very young. Where I got it, I was never sure, until recently a friend of mine played me a series of public information films that were shown on television when we were young (he collects such things and puts them on his laptop to enjoy at leisure). One of them was an animation in which a married couple sat on a cliff enjoying a picnic and watching a man drowning in the sea below (the thrust of the film was, don’t wave back - call the lifeguard). The husband called his wife Petunia, and I suddenly wondered whether that wasn’t where I had got this most unlikely name, because I have never met anybody called Petunia, or, to my knowledge, read about them. The subconscious is a very odd thing. The cartoon Petunia was a fat, cheery character, so all I seem to have taken is her name." (Cited from Pottermore.com)