Helping a friend with her trip, their first three days will be at discovery cove/aquatica/sea world, then onto disney. I have no clue what to recommend to her as I have never stayed near those attractions. They are a family of five
I would suggest that she check out the official Seaworld properties.....the Residence Inn SeaWorld, Springhill Suites SeaWorld, and Fairfield Inn & Suites SeaWorld are all generally very reasonably priced and offer a good value (with free breakfast, parking, wifi, etc.). There is also the Doubletree, Hilton Grand Vacations, Hilton Garden Inn, and Renaissance, but they are normally a little higher cost than the first three I mentioned (and don't include some of the aforementioned benefits like breakfast).
Staying at an official SeaWorld property will give a whole bunch of extra perks like free shuttles to the parks, free Quick Queue (front-of-the-line access to the rides), free show seating at SeaWorld, and more:
Another option to consider, depending on your friend's travel dates, might be Sheraton Vistana Villages. Its very close to the SW parks. It would give them way more space to spread out (two bedrooms, full kitchen, living and dining areas, in-suite laundry, two bathrooms, screened balcony), and SVV has a pirate ship-themed pool for the kids. Parking and wifi are both free. Skyauction currently has two bedroom villas for $499 or $599 (dates depending) for 7-night stays with check-in dates until the end of September.
Edited to add.....I re-read your OP, and see its only a three night stay that they need. Perhaps the Dreams Unlimited Travel rate would be a better option:
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