My 5 year old son has been prescribed this by the 'poo clinic'. He needs to take one sachet daily. Can anyone tell me anything about it? Is it best to given early on or later in the day? I know every child is different but how long did it take for it to work it's way through? My big fear is that the urge will take him when he's at school and, because he refuses to use the loo, he'll mess himself and end up embarrassed by the whole thing.