You can get a “stroller as a wheelchair” tag from guest services which lets you (as the name suggests) treat it like a wheelchair and bring it through the lines.
I also agree with Sir Duff about getting stroller as a wheelchair tag which also allows you to bring building where strollers not allowed like The Seas and others
A 14 yr old using a special needs stroller should not need a stroller as wheelchair tag because of the size of the child and stroller.
But, I agree with the other posters to get one - better safe than sorry. And, even if the CMs recognize it without the tag, having the tag will/should avoid some grief from other guests