Thanks, everyone, for your responses.

Sandra,
Thank you for the link, I will look further into that

Sorry, I forgot to mention that Neko will be 10 in March. He's been fine all his life, the murmur was just something that my vet noticed last time he went for his yearly checkup.

If she hadn't told me he had a murmur, I would've never guessed it for a second. Neko is his usual lovable self.

I will talk with my vet further about Neko when I take Tama in next month for his yearly check up.

(Poor Tama, he's still chewing himself apart...the move was just too much for him. He's improved quite a bit but still has certain spots that he will not stop going after.)

Thank you all again, I appreciate it.