My son has been able to use a spouted cup since 9 months old, but for the last 2 months has absolutely refused to drink anything from it, be it milk, water or juice - not a thing. I have always left a cup in the lounge where he plays and he would pick it up to drink, never much in one go, but by the end of the day it would be empty. I've even tried open cups of different shapes and sizes but it's made no difference. Now he doesn't even try to have a drink and if I try to get him to drink he gets upset and pushes the cup away. I am having to resort to putting the cup in his mouth for a second to get any liquid in to him. Obviously he is now getting constipated so it's much more important. I really don't know what to do or what to try next. Apart from not drinking he is eating and sleeping well and is acting fine. But when he poos he is quite distresed and it takes him 30 mins to 'go'. I'm adding liquid to all his meals but it's not enough. Help please...