I vaguely remember a time when I believed that there was a Santa Claus. My parents never let on that the fictional character wasn't real and until I was in first or second grade I waited anxiously on Christmas Eve for Santa's visit.
I recall vividly one such Eve. I was being a pill. My mom wanted me to get to sleep so she could do what parents do to keep the sprite elf's visit a mystery, and told me if I didn't get to sleep there would be no visit from Santa. The threat of getting a lump of coal in my stocking was real, as we still has a coal-fired furnace. Poor dad. He had to go down and bank that thing every night and then stoke it first thing in the morning.
So I weedled her into allowing the shade that was pulled down on the window next to my bed to be raised all the way to the top so that I could watch out that window for Santa and his sleigh to arrive.
Of course, I soon fell asleep. All I needed was a reason to really keep my eyes open, and then the lids slammed shut faster than a rabbit runs into his hidey hole.
The next morning I found a doll -- my first -- which I still have. It had the kind of eyes that close automatically -- quite a treat for me. I held that doll all day long on Christmas day.
One more thing. This must have been before I was 5 because my sister wasn't in bed with me yet. She was still in a crib.