Dogs Whose Names Didn't Change Even Slightly #11: Petra
The UK children's magazine show Blue Peter has been running since 1958, and introduced its first pet in 1962: a mongrel puppy. The show was only on once a week back then, and by the time the next show came around the dog had died.
Undaunted by the fact that this trick never ever works in sitcoms, they bought another one that looked like it and pretended it was the same one. Then they asked the viewers to name it, and they called it Petra. So Petra wasn't actually the first Blue Peter pet, as is always said, and strictly speaking nor did another dog take over the same name. But it's true she was the longest-serving.
Petra also briefly founded a dynasty, as her offspring Patch joined the show. I think we all remember where we were when John Noakes tearfully announced Patch's death. Yes: in front of the television.