A family of tortoises went into a cafe for some ice cream.
They sat down and were about to start when Father Tortoise said, "I think it's going to rain. Junior, will you pop home and fetch my umbrella?"
So off went junior for Father's umbrella, but three days later he still hadn't returned.
"I think, dear," said Mother Tortoise to Father Tortoise, "that we had better eat junior's ice cream before it melts."
And a voice from the door said, "If you do that I won't go."