joke for the night

I was watching yet another rerun of Everybody Loves Raymond, which is one of the best TV comedy shows ever, and Frank (Ray's dad) said this joke to Raymond that got me shaking my head for as long as I could.

Frank: Don't you know that Mark Twain had a son? Do you know what they called him?

Ray: (looks at Frank waiting for the answer)

Frank: They called him Choo Choo.

Choo Choo Twain!! Hahahaha.

*toinks*

Let's just hope I won't suffer from an LJK - Last Joke Syndrome.