One of my friends had baby recently "Baby Freya" as sarah calls her. After visiting her for the first time, Sarah was getting ready for bed as usual, singing to herself in her own little world "I'm a little girl called Freya, Freya, Freya. I'm a little girl!". About a month later, we went out for a family picnic and Sarah's Aunty Tor, who was heavily pregnant at the time, was there so we had the discussion of the baby in Tor's tummy and that it would be coming out in a few weeks. 
A couple of days after that, Sarah and I were playing on the bed and she stroked my tummy....."Have you got a baby in your tummy Mummy?" "No darling, Mummy hasn't got a baby in her tummy." "Oh!" she said "You just got a big tummy Mummy?"
Very funny and probably one of the few people who can get away with a comment like that!!!!!