The last time we were at WDW, it was my daughter's 4th birthday. We didn't know about any special treatment but that didn't stop it from turning out to be a great day.
First of all we had to decide which park we would visit because of her interests ... Magic Kingdom was the clear winner! We ended the afternoon with a late lunch/early dinner at Crystal Palace with Winnie the Pooh characters. This was a huge hit for my family as we had never eaten inside one the restaurants with a character meal. It was like being transformed into a peaceful environment while you barely noticed the hustle and bustle outside. We let the server know it was my daughter's birthday and they responded with enthusiasm, bringing her a piece of cake with Pooh, Tigger, Piglet and Eyeore while the servers all sang Happy Birthday.
I would definitely recommend you pick your favorite park and make advance PS reservations for a Character Meal. As we discovered, our late lunch cost a bit less than dinner, and we felt that it was better to celebrate later in the day than a Character Breakfast when most restaurants are fully booked and maybe too busy to offer you extra attention.
