Once upon a time there were 3 balloons - mummy balloon, daddy balloon, and baby balloon.
Tired of baby balloon creeping into their bed every night, mummy balloon told him "Tonight you must stay in your own bed!".
But when he was sure his mummy and daddy were asleep, baby balloon crept into their room and tried to squeeze into their bed.
But try as he might he just couldn't fit in. So he undid his mummy's knot and let some air out of her.
But, to his dismay, he still couldn't fit in, so he crept round to his daddy's side of the bed, undid his daddy's knot, and let some air out of him, too.
Again he tried to squeeze in, but he still couldn't quite fit.
So he undid his own knot, and let some air out. Then he fitted in nice and snuggly, and fell sound asleep.
When his mummy woke up she was furious!
"I am so disappointed!," she shouted.