Greetings, Guillermina! Thanks for visiting the Disney Parks Moms Panel and asking your question!
My daughter is almost 5 years old and she certainly needs a stroller when we visit the parks. Often, we are in the parks from the early morning until the late afternoon and by that point she is completely wiped out. So I definitely understand your need for a stroller when you visit.
Strollers are indeed available to rent at the Walt Disney World Resort theme parks and Disney Springs. You can rent a stroller for a daily fee, or pre-pay for the length of your visit for a slight discount. Keep in mind that rented strollers must be returned to the rental location before leaving the theme park. So, if you think your daughter will need the stroller to get from the park gates to transportation or around your
Walt Disney World Resort Hotel, then you might consider renting a stroller from a third-party vendor.
Disney has partnered with a few vendors that will provide you with a stroller rental for your entire vacation (the list of vendors can be found on the stroller rentals page linked above). They will deliver the stroller to your hotel and you are free to use it anywhere around the Walt Disney World Resort where strollers are permitted. Then the company picks it up from your hotel on your last day. I used Kingdom Strollers on our last visit and was really happy with the convenience. One bit of advice if you rent through a third-party company is to include a rain cover with your rental! So many times we would come out of an attraction only to realize that it had rained and our stroller was soaked. After that, we learned to put the rain cover on each and every time we parked it.
I hope this information is helpful! Have a magnificent time at the Most Magical Place on Earth!
-Linda