We have been making our babies bottles up by boiling water, measuring it out in bottles and having 4 made for through the day and then again same for the night. We don't warm the water back up when she is ready for a feed as she has always had it cold so we put the powder in the cold water and shake and that's her feed. It's super easy and she takes it no problem but a friend has told us we should be warming the water again before making it. Has anyone else done it our way or are we going to have to start heating them? It seems silly to make more work when she takes it cold?