This is what I heard from "most of the CMs" at 1-407-WDW-DINE, for children under 3:
1). You may share your plate with your child at Al La Carte restaurant (if you decided to order something from children menu, of course you have to pay OOP).
2). They can eat free at any buffet/all-u-can-eat type restaurant, you can just grab a plate and feed them.
However, one CM (the only and one, maybe a weird one) told me that the above isn't necessarily true - it all depends on the restaurant

I am not sure about this exceptional case, maybe she was referring to some fine dining ones, like Victoria & Albert?
I am going there in March, with DD2, hopefully in those family-style restaurants, they serve everything in a platter. Hopefully the server can provide some food for my DD from children menu (I am talking about Garden Grill, LTT) such as Macaroni and Cheese - let's see
Oh yes, for those who are on Dining Plan and have travelled with kids under 3, do you have to remind your server that your child is under 3, before he/she brings the bill? I saw quite a few posts that toddlers are being charged for 1 TS credit - I just want to avoid trouble (waste time) to request correcting the bills etc - this is our annual vacation
