A connection can be: they are all about flowers, they have the same drummer, they all sing about Pink Mushrooms, or they are all kids from famous parents. Just to give an idea of what a connection might be.

I want to hear the some about Pink Mushrooms man!! A great post as always, and was delighted to see it early and get in with my guess that they were all cover songs by Elvis, who wrote almost none of his classics at all. He did co-write 'That's Someone You Never Forget' and 'You'll Be Gone' as far as I know.