Hello ANA!
Welcome to planDisney! I have two little ones who are not so little anymore and I still must use a stroller when I visit Disneyland Resort or Walt Disney World Resort. It's become my base of operations for the entire trip and a safe place for them to relax. It also is very good at minimizing the potential whining and breakdown moments greatly.
Unfortunately,
stroller wagons are not permitted in Disneyland Resort. Anyone seeking to bring one in for their child who has a disability or if the stroller functions as a wheelchair will need to reach out to
Disability Services to get all the best information to aid their family. They could be the only exception to the no stroller wagon rule and they will be evaluated on a case-by-case basis and given a special tag for their stroller. I'm sorry I don't have better news for you as I'm sure your little one loves their wagon but if you have an alternate stroller that meets the size requirements please be sure to bring it. If you don't have another one you can
rent a stroller when you arrive. I recently rented the strollers for my kids from the Parks and found them perfect for older children. When they were younger, the single or double stroller I already had was better suited as they reclined and had a lot of storage space. You never know when they need a nap or need their comfort item.
Make sure to label the stroller and make it distinctive with ribbons, a balloon, or glow stick necklaces so that day or night you can find it in the sea of strollers in the Parks. It also makes it more festive for your son! My favorite item that I always have on my stroller whether it is my own or one I rent is my stroller hooks. They attach to the handlebars with Velcro and are very sturdy hooks I can attach light bags and popcorn buckets too. Just make sure it is not too heavy as the stroller could tip. (That would not be pleasant.)
I hope this helps and you have a great time this weekend!
Happy Planning!
-Nimmy