Alex is lucky, because he is part Dutch he has three gift getting events. First the Sinterklaas visits him, then Santa Claus and finally the three kings. All bearing gifts. Alex clearly remembered Sinterklaas the best, and I was wondering why.
I think the answer lies in Alex experience with the three events. All events involved some great arrival. Sinterklaas arrived in Cadillac, with a drum band. Santa Claus arrived in a mini helicopter and the three kings arrived in three boats. Alex had his picture taken at all three events, and every saint was dressed up and looked impressive. Soon after each arrival Alex received a few gifts (at night) that were delivered in some magic way.
The only difference that made the Sint stand out was that when the Sint arrived he shake the hand of Alex (the picture moment, just like Santa and the Kings) but this moment was accompanied with a little present and some candy. Enough to make it a memorable event.