DD1 never took a bottle and I wonder whether we missed the window when it would have been possible because I didn't want to mess up breastfeeding. I would like DD2 to have a bottle occasionally, so don't want to miss the chance this time, but again am anxious not to risk her rejecting breastfeeding in favour of bottles. She's not quite 3 weeks old, is 6 weeks the general guideline? What does 'established' actually mean?