"Mummy Polar Bear And Baby Polar Bear" joke

A mummy polar bear and a baby polar bear are sitting on and iceberg watching an ice flow go by.

The baby polar bear says to the mummy polar bear, "am I a polar bear?"

The mother says, "of course you're a polar bear!"

They sit silently for a while, and then the baby polar bear repeats his question, and gets the same answer.

A little while later the baby polar bear says, "am I REALLY a polar bear?" By this time the mother is a little irritated, and says, "of course you're a polar bear! Your dad is a polar bear, your brother is a polar bear and I'm a polar bear, so you're a polar bear! What is all this nonsense?"

"Well, if I am a polar bear, why am I so bloody freezing?!"