It's funny, my parents did exactly the same thing and while I enjoyed playing along I can't recall ever believing a word of it. I'm not sure how my gut so quickly got to the truth. Maybe people deep down follow Occam's razor, though more likely I just got it by osmosis.
To tell you the truth, I think back to that when I question my gut to this day. I'm thankful my parents never lied to me outside of it, but the wonderful thing about Santa is that everyone is in on the conspiracy, so if you can see past it you'll only ever be more confident in the truth when you find it, without taking it for granted. If it means anything from a random person on hacker news, I benefited from being told that Santa existed, and from the sound of it your daughter will too.
To tell you the truth, I think back to that when I question my gut to this day. I'm thankful my parents never lied to me outside of it, but the wonderful thing about Santa is that everyone is in on the conspiracy, so if you can see past it you'll only ever be more confident in the truth when you find it, without taking it for granted. If it means anything from a random person on hacker news, I benefited from being told that Santa existed, and from the sound of it your daughter will too.