Hello, Christine,
What a great dream your son has! At
Disney's Art of Animation Resort, there are often animators in the lobby of the resort doing demonstrations. There are also classes offered on how to draw characters. To help you find out if anything is offered during your visit, I'd contact the resort as your trip draws closer (the number is in the above link).
There have also been demonstrations in the past at the
Art of Disney at Disney Springs and the
Art of Disney at Epcot. You may want to stop by any of the theme park Guest Relations to see if they could call on your behalf to see if they could find out if any demonstrations will be happening during your trip.
If you'd like a little fun at home before your trip, you can search for
How to Draw Disney on YouTube. You should come up with many videos of Disney Animation Artists (from the now-closed The Magic of Disney Animation attraction at Disney's Hollywood Studios) showing the steps in drawing popular Disney characters. A little blue square with a D in it should help you to know it is a Disney Parks video.
Wishing you a trip filled with many unforgettable moments! -
Kara