It was always just there, and I never questioned it. Obviously, because I was raised Christian and went to church every Sunday. I participated in MANY church events, they were very nice, and helped my very poor family in every way they could. It was an incredibly supportive environment and I really enjoyed it. However-
When I was 6 I discovered the Easter bunny wasn't real when I found a box of Easter chocolate under my parents bed the day before. I cried all day, but I got over it, and enjoyed the hunt/chocolate anyway.
When I was 7, I discovered Santa Clause wasn't real when I woke up late at night and went downstairs to watch TV instead of trying to sleep, and my parents walked in the door carrying garbage bags and boxes full of donated toys. They pretty much explained right then and there that he wasn't real and told me to go back to bed. I was pretty okay with it, honestly.
Shortly after, at about age 8, I began to start questioning everything my parents had told me that sounded "magical" so to speak. I didn't tell them about a tooth that had fallen out and I hid under my pillow as a test. I kept it there for a week, probably as a last ditch effort to keep my innocence, before I caved and told my parents I knew the tooth fairy wasn't real either. I kept all my baby teeth in a jar after that.
Finally, that brings me to the age of 10, when I was no longer allowed in the kid's playroom, and I was expected to actually study the bible and do homework on it. That was when I realized this wasn't just another one of those things, but it was serious. The bible made no sense to me whatsoever at the time, probably because ALL the stories sounded made-up at that point, and all the adults weren't just pretending about this one. They were playing pretend that this wasn't pretend, which was WAY worse, and I was fully expected to take it just as seriously.
I didn't know what a "cult" was back then, but I got extremely strong cult vibes and flatout refused to attend church anymore because of it. It was just too damn absurd. I lost a lot of friends, had some laugh in my face when asked if I could go to their birthday party(never spoke to that kid again) because I didn't go to church anymore. No regrets though. I'm much happier playing reality and not pretend.
TL;DR No more playroom, no more Jesus.