"Don't worry about that bug, it has no mouth parts" my father used to say, when there was some

scary looking insect on us. He had always been interested in entomology and knew better, but he was wiser in the ways of fatherly comfort for an alarmed kid. His tactic nearly fell apart, though, one night in Tunisia when three of us awoke with giant cockroaches crawling on us: we kids could clearly see their 'mouth parts' inches from our frightened faces!!

Years later, I tried that on my own kids several times, and they just said "Yeah, right, Dad"