Every child has fears. It's reasonable because a child has not yet developed comprehension of the world around them and how it works. Shadows on the wall at night that move are ghost or monsters that will attack when they close their eyes.
My fears as a child went deeper. Things I could see with my eyes did not cause me to fear. Things I could not see did. Things I could feel but didn't know where they came from caused me fear, like sounds in the night.
Now I am going to share with you, my strangest childhood fear. Poop. Most children when learning how to go potty on an adult toilet fear being flushed down. I feared that as well. But I also feared my poop. I was always a constipated child. I didn't like water, or veggies, just milk, meat, and bread. Pooping was painful and it left ugly lumpy loud dropping clumps in my toilet. The would float on the water. I know because I always turned around to watch and make sure they went down when I flushed. They'd spin into the funnel of water and out of view never to hurt me until I went to sleep and dreamed.
When I slept, larger than life, okay really just larger than me, stinky, lumpy monsters would stalk me throughout my house. Tunnels would open and pathways through closets where none would actually exist outside my dream. I would escape but even though they wobbled, somehow they were always right within arms reach. After I ran out of hiding places one would grab my shoulder and I would wake in sweat filled terror.
Of course, mom would come and rock the fearful tremors away and all would be safe again to sleep. Mom would return to bed and I would fall asleep happy that mommy had chased away the giant poop monsters.