Reminds me that strangely enough, being afraid of clown is apparently a not uncommon phobia.
. Some parents expose their children to the circus, or even birthday party clowns at too young an age. Many such clowns have a scary designed, supposedly funny face, and they stick that face right in at close range to the infants and really young children to make sure they don't miss it. But that can be very traumatic. The natural instinct of a Human is that the unfamiliar is likely to be a danger, so they recoil from it in fear, and keep a lasting memory of that to always remind them of that potential danger in the future. I would guess that most children with an extreme (neurotic) fear of clowns got that from an incident that happened before the age of five.