It might not be a suger problem, it could be additives, I used to be awful at night when I was young so my mum changed the mixing juice she gave me and found that two were noticably worse than the others for my behaviour so I'm very carefull as to what I give to my own sons. The 'mammy mammy' thing,I know exactly what you mean, my oldest is 2&1 and we'r going through the same thing and I have no idea how to deal with it.