Imagine Monsters

So the Mud Puddle is at that age (which, oh by the way, TOTALLY snuck up on me) where he has started imagining things.
There are times as a parent that you brace for, the first time they see a clown or a person dressed up as something else (Santa Claus or an Acorn in our case), the first time they go to the movies or an amusement park. How will they react? What will happen? Shyness? Smiles? Screams of Terror?
Imaginary friends (or foes) was one of the items on my Bracing for It list.
We have friends whose daughter is one of the sweetest, smartest children I know. When she was three and started having imaginary friends they were dragons, and she would work herself into a frenzy. SCREAMING when she 'saw' them in the kitchen or the bathroom. Haley Joel Osmet via the Sixth Sense had nothing on her. She didn't see dead people but boy those dragons were real to her.

So fast forward to the Mud Puddle, how would he react? What kind of substance would I need to start abusing to get through this?
Luckily, he is very matter-of-fact about his imaginary animals. He 'saw' one the other day.
"Mommy, there is a monster."
"Where, over here? What color is it?"
"Lellow"
"What should we do with it, monsters aren't allowed in the house. Should we put it outside?"

I guess I could have let him stomp it, like he does with ants, but some of my buddhist phase must have stuck with me when it comes to monsters (were it not for my love of shoes, purses, and all things Ann Taylor I could have lived out my days barefoot on a mountain meditating and loving fleas) so we put it out on the lawn. It seemed to fit into his hand which must mean it is a small monster.

And it hasn't shown up since that initial sighting, but I am sure this is just the tip of the iceberg.
I had a gang of animals that lived in the bathroom and kept me company (and told me to lock the door that didn't have a key and required my father to climb a ladder and come in through the window - on the second floor - and yes, this happened more than once).

Parenting, in my rookie estimation, is a series of bracing for the worst, hoping for the best and just improvising no matter which way the tide turns.
And being sure to document it all for future blackmail purposes.