Hi Sylvia! How much fun - so I bet you are known as the "favorite aunt" now, aren't you?
There are several character dining experiences that she may like. Does she like princesses? Then check out Cinderella's Royal Table at the Castle in the Magic Kingdom, or Akershus Royal Banquet Hall in the Norway Pavilion in EPCOT. Both are excellent.
If she is a Mickey and Friends fan, then I highly suggest Chef Mickey at the Contemporary Resort. Or, if Goofy floats her boat, then swim on over to the Beach Club Resort to the Cape May Cafe. If it's Pooh and Friends she loves, then the Crystal Palace in the Magic Kingdom is the place to go!
If she is into getting the Princess Treatment, then consider the Bibbidi Bobbidi Boutique, where they will fix her hair and makeup just like a princess, with the option of purchasing the full costume. You also mentioned you are in the Pirate Room, so the Pirate's League may be more her style, which is at the Magic Kingdom. They will give her the full pirate treatment there!
You may also want to just spend the day shopping together, if that's her thing, in Downtown Disney & Marketplace. There are some wonderful shops and restaurants there.
Disney also provides some special ways to celebrate, and you can explore those on the Disney website by clicking
HERE.
More than anything, I am sure she we will enjoy just spending time with you - and Walt Disney World will just be the icing on the cake! I am hoping that you will create many magical memories together on this special trip!