Me too...ever since I have had kids I tear up at all the milestones in their life, even now. DSeaU graduation, Dreams show, Til we Meet again, sadly enough, while we were eating breakfast right before we left the ship last time, I was sitting there crying. Yes, I know ridiculous. But I knew that the cruise we had just finished would be special because of the things we had done that time and the ages the kids were at that time. Next time (this trip) would be different because they would be older, maybe wouldn't want to do as much with us, and just a different experience. They were happy tears, but I felt so silly sitting there crying. It goes back to "Laughter through tears is my favorite emotion."
My favorite Disney memory ever is when my DD was 2. We were leaving the park after a long day from our second trip to DL. Right before we were headed into the train tunnel to exit the park, Mickey came over and gave her a big hug and shook her hand. I told Mickey that he was her favorite and he grabbed her hand and motioned for us to follow him. He took her to the annual pass center inside the park and at that time they put your picture on it. Well, he had them take his picture with her and put it on a plastic card and gave it to us. I still have that card and think it is the coolest thing ever. She looked so cute walking next to him and holding his hand. I don't think I remembered to get a picture of that part, but it is cool.
So yes, if you see me crying at some point during the cruise, it will probably be tears of joy because I am a little too emotional sometimes. (yes, my husband appreciates it as well).