My 5-year-old daughter has been worried for weeks about going on vacation to her grandparents' house (150km from home) but not about staying there, in case her parents call her too much and ruin the fun.
1yo - a toy trumpet that was sold at a carnival that sounded like a satanic battle cry and one kid was spending every single breath out blowing that fucking thing, causing my kid to freak the hell out.
7yo - a speck of dirt on her skin that she thought was a tick
2 years old - a puppet at a puppet show story time. She was in tears at the first song then for the rest of the show she kept repeating “puppet not bite you” and “puppet stay in blue box”.
But then later said “I need more puppet” so maybe she got over it.
Pretty far in the past now, the kid has gotten a lot more resistant to fear over the years.
But, back when they were about 7, ghosts were the big fear at night.
Solution: ghost incense. One of those things I pulled out of my ass in the moment that worked like magic.
The kid didn't want to go to bed. Was asked why. The answer was that they didn't want ghosts to come get them.
In a rare flash of genius, I said "Well, I can fix that. Ghosts can't go anywhere when you burn a stick of a special incense. I keep a box of it around for emergencies."
We lit some nice smelling stuff, and said the magic words, and that was that.
Now, the next day, we had a nice conversation about how ghosts aren't real, and even if they were, they're ghosts, they can't hurt anything. The kid asked if we could burn the "ghost sticks" anyway, just in case we were wrong lol. So it became the bedtime thing. When the kid would get tired, they'd show up with a stick of incense and ask me to light it.
By the end of that summer, the kid had said they weren't scared of ghosts any more, but can we use the incense anyway, it smells nice.
Sometimes, trying to convince someone that their fear isn't based in reality is not only impossible, but counterproductive. For a kid, it's all about helping them manage the fear, give them control of it.
Man I can't wait to break out my D&D Monster Manuals and be, like, "well, it says here that ghosts can't be killed by normal weapons - or at all, really - but you can convince them to go away by asking nicely, so if one shows up just try that. They might ask you to do them a favor, but run it by me, first."