One of my girlfriends has a single goldfish. Her daughter calls it Willy when she's looking at it from one side of the tank and Wonka when she's on the other side. Periodically she swaps sides. When asked about it she says "Goldfish are mysterious creatures."
I asked her one time how she knew the fish was a boy. She looked at me with this serious face and said "Goldfish are much more open-minded than you are."
She's 9. Talk about precocious!