Liberace

As silly as you may think my inquiry may be I would like to ask about a phrase I heard while watching a Bug's bunny cartoon. In this episode he's playing the piano, pauses to the camera and smirks to say "I wish my brother George were here". Who was "George?
I'm sure when this first aired 50+ years ago-- people got the joke.
It's amazing to me how much of the humor I didn't get when I watched it as a child.
(except for this one). Thanks.

It refers to pianist/showman Liberace's brother George.