Aww thats very sweet... and im sure if you would like you can request a special meet and greet before the parade takes place so that he can meet his favourite disney character(s). Im not sure where you could request as I worked in parade department and usually if we wanted meet and greets we'd ask our team leaders, but im sure at city hall you can ask. Its very cool, as its personal and 1 to 1 interaction, and the characters love spending time with special guests. Just something to consider for you.