Hi Charles,
Sofia the First and Doc McStuffins are among my daughter's favorite Disney Junior characters. I am sad to say that at this time, these characters are not available for a meet and greet. However, there are other Disney Junior Characters such as Jake from the Neverland Pirates and Handy Manny which can been found at the Animation Courtyard in Disney's Hollywood Studios. On the bright side, Disney recently announced plans to add the stories of Sofia the First and Doc McStuffins to the Disney Junior - Live on Stage! Show in mid-February.Be sure to check back periodically for the latest Character Experiences!
As for your little man, here are a couple of "must see attractions" my two boys can't live without: "Toy Story Midway Mania" at Disney's Hollywood Studios; "Peter Pan's Flight", "Buzz Lightyear's Space Ranger Spin" and the "Magic Carpets of Aladdin" at the Magic Kingdom, "The Seas with Nemo and Friends" at Epcot and "The Boneyard" play area at Disney's Animal Kingdom!
As for dining, I have to recommend Donald's Dining Safari, which is a character dining (either breakfast or lunch) at the Tusker House at Disney's Animal Kingdom. Your kids will love meeting Donald Duck, Daisy Duck, Goofy and best of all, the mouse himself, Mickey Mouse!
Happy Travels,
Yael