Hi Sara,
Thanks for visiting the Disney Parks Moms Panel with your question. We on the panel love to help guests plan magical Disney vacations!
Given the configuration of your family, if you did purchase a Disney Dining Plan, you would need to do so for the two adults in your family, plus one child (the four-year-old). As your other two children are under three, they are not eligible for a dining plan, so you do not need to buy one for them. They may share the adult meals for no charge. I do not know how much your little ones eat; however, if you think that they will be happy nibbling from your plate and your husband's plate, this might be a good plan. You are also always welcome to purchase additional meals while you are at a dining location. For instance, if you do purchase the dining plan for yourself, your husband, and your older child, perhaps at each restaurant you could pay out of pocket for one additional child's meal for your littlest children to share.
Given this, I think that it depends on how your children eat for your decision on whether to purchase a Disney Dining Plan. Please do note that there are many different options for dining plans - including a Quick-Service Plan, Dining Plan, Deluxe Dining Plan, Premium Dining Plan, and Platinum Dining Plan. You can download brochures about each at the
Disney Dining Plan website so that you can compare and see which might work best for your family. Then consider how much your littlest ones eat and what you might eat each day as a family at Walt Disney World to see if you think that it is a good deal for you.
I hope that these thoughts are helpful for you, Sara. Have a wonderful time planning your vacation, and please do not hesitate to ask if you have any further questions!