Are you Afraid of the Dark?

Ok, so its November and my three year old still wants to wear her swimsuit.  Swimming lessons have been over for a month.  It's too chilly to wear it to the beach.  We have been keeping them locked up.  Her closet has a lock on the inside.  I don't know why, but it has come in helpful.  She has, like, four of them.  She has given them names.  Color, blue, brown, and I'm not really sure what she calls the two piece.  Anyway, she still wants to wear them.  The other day, she had a conversation about it with my hubby.  She told him the "color soup" was afraid of the dark.  It needed to come out of the closet.  I find this hilarious.  I wish I could have that conversation with her.  I mean, I don't really know how to respond to that, but find it amazing my child is thinking up ways to liberate her swimming "soups" from the dark closet.  She knows there is a key to unlock the door; so she sticks things in it (bobby pins, belt buckle, anything small and pointy) to try to open it.  She is pretty smart.

Princess in her "colors" suit

How do you reason with a three year old?  Should you even try?  Hubby told her the swimming suits like the dark.  How would you respond?