Who wants to be a Millionare joke

A six years old boy and his dad went to the newsagent to by lottery tickets.

Boy said to the man at the counter "we are going to be millionaires!"

Man replied asking "Do you want to be a millionaire?"

"Not really... ."

Hearing this the father felt really proud of his kid, thinking he is very wise at such a young age.

Then, the boy continued his answer "A millionaire can't buy everything... I want to be a billionaire!"