DS, will be 4 for our December trip, has autism. I'm trying to think of a good way to keep him seated at restaurants. He is way too big for a high chair, and I don't remember many boosters with restraint belts at Disney (he is getting too big for these anyway). I'm looking for something that is portable for seating to keep him in place. He can undo a standard buckle such as the ones on the strollers, but I think he will stay in place on the bus and in the stroller. I'm mostly thinking about restaurants...
I've seen two things. One is called a portable travel vest that goes over a standard chair in a restaurant. This one is very portable, and cheap, but I'm worried he will be too big for it? The other option is one of those portable car seats, which would hold him for sure but would be heavier/bulkier to carry around. I'm leaning toward the portable car seat, like the ones at One Step Ahead. Does anyone have any ideas? DS does calm down considerable when he is restrained somehow.
I've seen two things. One is called a portable travel vest that goes over a standard chair in a restaurant. This one is very portable, and cheap, but I'm worried he will be too big for it? The other option is one of those portable car seats, which would hold him for sure but would be heavier/bulkier to carry around. I'm leaning toward the portable car seat, like the ones at One Step Ahead. Does anyone have any ideas? DS does calm down considerable when he is restrained somehow.

, wife to Darrin
,mom to Hannah
10, Chandler
7, and Dustin
6
I'm worried if the restraint is TOO obvious it'll be embarrasing. It was fine when we could do a booster with a belt that buckled--no one stared at that. I just don't remember many of those in WDW. If I could find something that looked like a booster but was portable... I love the idea of those cloth ones for toddlers, the portable ones that fit on any chair. I just need to figure out if it is big enough for him. We may just have to work a little harder on the restaurant manners and staying in our seats while we eat. Easier said than done. 