Dec has been getting his milk in his cup for about 1 week now and he is loving it, I am thinking of getting rid of all the bottles now, just kept them in case he needed them again. He is 101/2 months. I think most people do it between 12-18 months but it is best for their teeth to do it as soon as possible, but I wouldnt make an issue out of it Caitlin only gets 2 bottles a day doesnt she?? Well that wouldnt do any harm to her teeth it is only if a child is getting all drinks in their bottle that the most damage is done. xx Good luck. Oh hows the crawling going?? bet shes into everything now !!!!! Lol