The Princess Storybook Breakfast in EPCOT is an option if you can not get Cindy's but can be booked at 120 days out.
There is also 1900 Park Faire that has Cinderella, Prince Charming, Suzy, Perla and the Fairy Godmother for dinner. It is a buffet.
Crystal Palace serves breakfast lunch and dinner with Pooh, Tigger, Piglet and Eeyore. All are buffets.
Chef Mickeys has buffets for breakfast and dinner with Mickey, Minnie, Goofy, Chip and Dale and sometimetimes Donald and Daisy Duck.
Donald's Breakfastasourus is a guaranteed Donald in AK, a buffet.
My niece and nephew, now 5 1/2 but 3 on their first trip, just go along with the adults and usually there is something that they will eat as all restaurants usually have the standard kid menus.
Check out wdwig.com for restaurants, menus and prices.
Have fun!