We too have two autistic sons. Having just returned from DLP they did ask us for prove of disability, which we carry with us. They gave us a GAC pass and a booklet which stated that evidence of disbility had to be provided with a doctors letter dated within the last 90 days in English or French. The pass was great. We were turned away from Buzz lightyear ride, but went back the next day. They just told us they were too busy.