Advent

We bought a chocolate filled advent calendar this year. The kids and I had a long discussion about how to decide who opens which day. We decided to go oldest to youngest so that Hazel would not know what was going on for the first week. The goal here was to not let Hazel sneak everyone's chocolates. The plan worked wonderfully she didn't even know the chocolate was there for the whole first week. So on her assigned day we introduced her to the calendar and explained that "today you get to eat the chocolate behind this door and then in 1 week after everyone has another turn it will be Hazey's turn again" I think she understood. We even showed her which door would be hers to open. So for the next week every morning and every afternoon after her nap she would come ask "Now is it my day?". She waited so patiently and didn't sneak a single chocolate. So on Dec 16th it was finally her turn, everyone was so proud that she had waited! Dec 17th it was my turn again, and I went to open my chocolate. WHAT?!?!?! Every door had been cleaned out! (except the24th I think because it had a double door and she couldn't figure out how to open it)
She ate all the chocolates.

How do you discipline that? I tried a couple things, finally I bought another calendar (considerably cheaper at this point in the season) and the kids are doing it without her. So they all had 3 chocolates this morning with their breakfast.