Hi Helen!
Great news that your partner can join you! Walt Disney World is so much more magical when all of your family can be there with you!
Since the addition of your partner will put you over the occupancy limit of your room, you will need to either book a second room or try to book a larger room such as one in a
Deluxe Villa which features 2 separate bedrooms. I usually try to price out each option on the Walt Disney World website before making my decision. This helps me plan which options make the most financial sense for our family.
When it is time to update your reservation, the easiest way will be to call (407) 939-1936. When you call, a Cast Member will help you change resorts, book a second room, and adjust the guests in each room, if needed. Also, if you do opt for two separate rooms, you can always request adjoining rooms (rooms located next to each other) or connecting rooms (rooms with an interior door which connects both rooms). While the request cannot be guaranteed, I've always found that Disney goes above and beyond to honor these requests.
Of course, if you would prefer not to call and talk with a Cast Member, you could choose to simply
book a second room online, and then modify your existing reservation in My Disney Experience. The downside to this is having to take a number of steps and modifications to arrange everything. You would also then need to call at a later time to make a room request, if desired. Personally, I would rather just make one phone call and have all the details taken care of! It really does simplify things!
Good luck on adjusting your resort plans. It is a great reason to make a change! Don't forget to add your partner to any dining reservations or other plans as well!
Let us know if we can help with any other trip planning details! The Disney Parks Moms Panel loves to help!
Kathie