Hi!
Thank you for writing to the Moms Panel! You can get the latest information on the Disney Dining Plan
here. However, I don't know if it makes sense for your family or not. You would have to consider how you normally dine at Walt Disney World (Table Service, Quick Service only, both, how many snacks each day, etc) and calculate what it would cost vs. what the Dining Plan costs. You can find menus with prices for almost all of the restaurants at Walt Disney World at the independent site AllEars.net. It's a great site and I'm a big fan. Their website is www.allears.net.
Be sure to have Advanced Dining Reservations if you are considering the standard Disney Dining Plan or a more expensive plan. Ideally, you want to make the most use of any Table Service credits by eating in the restaurants that are most interesting to your family!
If you do go with a Disney Dining Plan, your baby can absolutely share with you! In fact, guests of any any age can share as you do not have to use all of your meal credits at every meal.
Have a magical vacation and write back if you have any other questions!