My daughter is starting nursery for a day next week and they have asked me to bring all the bottles needed for the day already made up, as they are not allowed to mix up formula even when the powder is already measured out. They say all the mothers do this with no problems. However, whenever I try and find out any information about this, it says to make up each bottle individually when needed as making up in one batch for the day could make your child ill. What are these other mothers doing that I'm not realising? I'm sure their children aren't falling ill, but I'm at a loss to work out what to do. Any advice gratefully received.