Hi Sebastian!
As your child is under the age of three, she does not need to have an admission ticket for entry into the theme parks. You will need to make sure that she is counted when booking your dining experiences. This is so that the host/hostess at the restaurant can be sure to accommodate a high chair/additional seating for your daughter.
As your daughter is disabled, you can head to guest services and ask for a Guest Assistance Card. The GAC will allow your party to enjoy the attractions and experience the theme park in her comfort zone. It will enable your party to access the attractions through special entrances/exits which will provide your daughter with a more comfortable wait time for attractions.
Make sure that you bring your child with you, and you explain to the Cast Member exactly why you are requesting a GAC, and what accommodations you are requesting (cooler place for you son to wait). This way they can assure that you are being given the correct GAC. Should you have any difficulties with the GAC, don't hesitate to ask for a supervisor. Disney's goal is to provide guests with wonderful and memorable experiences, and they are willing to do just that. It always helps to bring a note from the doctor explaining what your child's diagnosis is, as some disabilities are not always obvious to the outside eye. Remember, your GAC is valid for the entire duration of your stay.
Did you know that we answer questions in Spanish? Visit us on the Moms Panel en Español page, linked below.
Moms Panel Español
Hope this helps you plan your magical vacation!
-Malanie