A 3-year-old is not too big for a stroller, especially when visiting a high-walking destination like a Disney theme park. While a toddler might walk independently at home, a typical day at Disney World involves walking between 8 and 12 miles, which is far beyond the physical capacity of most 3-year-olds. Having a stroller provides a safe place for them to nap, shields them from the intense sun or rain, and gives you a convenient spot to store bags and snacks. Disney’s official rules allow strollers up to 31" (79cm) wide and 52" (132cm) long, so most standard and jogging strollers fit easily. Many parents find that even 5- or 6-year-olds benefit from a stroller during a week-long vacation. If you don't want to bring your own, Disney offers daily rentals, though third-party rental companies often provide more comfortable, padded options that can be delivered directly to your resort.