We had the same experience a few months ago with Carina as you had it recently with Anthony (he remembered fairly well what is behind the little door). During our trip to Seoul in October last year we passed by an icecream shop only once, without stepping in. 3 weeks later we had to take the same way and Carina insisted to show us the way to the icecream shop. Of course we have been very surprised since we had no idea what she is talking about (we forgot already completely). We asked her to show us the direction. For her it seems to be a matter of trust and honor. She started to run (like launching a rocket) and stopping every 25m to tell us again that she knows the way very well to the icecream shop. We arrived quick (!!) and well and are still wondering how well she remembered.