Good question ... and my thoughts are NO, don't get rid of it.
Leave it in. The dog was a legitimate dog, it lived, and "erasing it" is actually a falsehood of sorts.
Not to mention this database might be the only record (and memory) of its existence.
In fact, I have purposely added dogs of mine, that I loved, but that died prematurely for one reason or another ... if only to "let their memory live" somewhere.
Jack