Hi Christina!
Thank you for visiting the Moms Panel!
You can request a Guest Assistance Card from Guest Relations in any of the theme parks. Guest Relations are usually located towards the front entrance of the theme parks.
While documentation is not necessary, it does help to have a note from your doctor so the guest services cast members know exactly what type of assistance might help you.
A Guest Assistance Card will not guarantee you immediate access to a ride or an attraction, but it could enable your son and husband, and up to four other members in your party, access to alternate entrances to attractions and on most rides will let you in without having to stand up in long lines or walk long distances. It may also allow you somewhere to sit, perhaps in a quieter area, while waiting at an attraction.
The Guest Assistance Card is good in all of the four theme parks of Walt Disney World for the length of your stay, so you only have to get it once per vacation.
If you have any other questions, please come back and ask me - I would be happy to help you plan your magical vacation!