With kids as young as yours I would ask their doctor what he recommends. I know there is kids dramamine but it will put them to sleep . But I would ask the doctor before even using that.
I do know that most kids do NOT get sea sick. it has something to do with their inner ear is not fully developed yet so they dont get affected like adults do. I know on board the ship the doctor suggested green skinned apples and keeping a full tummy helps kids if they get queasy without any drugs. I have also read of people taking ginger pills for sea sickness. Again I would ask the doctor first. But as young as they are I'll bet they wont even get sick at all!!!
Since the patch made you blurry eyed, have you tried the bracelets. I understand they work quite well and they work on pressure points instead of giving you drugs in your system.
I have never tried these remedies myself, I have never been bother so far. (keep fingers crossed) But I have known lots of people who have done all these remedies. I guess different things work for different people.
I wish you all the best, but honestly as young as your kids are if they get ill, they will be in the minority.