I use both a stroller and the cute leashes. My DS5 has a bigger backpack/leash from Jeep that he can actually carry quite a bit in if he wants. Leashes are great, even for que's because little one's don't like to stand there and wait. My DS2 would run in a line to get up front if given a chance. I know you will have a wheelchair, but there is still a lot of waiting involved with that. Sometimes I still carry my DS2 in my ergo carrier too, depending on how wild he's feeling that day. Definately take pictures in the morning and have your number where it can be found. Also, let the older children know who to talk to, if they were to get lost.