My daughter was not good with transitions. So, what we did, based upon the advice of others, was to still keep the bottle, but gradually decrease the amount of formula in it and mix in more whole milk. For example, if she was taking a 6 ounce bottle, we would maybe start with 4 oz. of formula and then 2 oz. of milk. Do that for a few days. Then go to 3 and 3. And, then 4 of milk and 2 of formula. And keep decreasing the formula until it was all milk. I think she got used to the taste easier that way. Then after a few weeks or so of all milk, we got rid of the bottles by around 12 months. If she will take a sippy cup well, try it with a sippy cup instead of the bottle. However, we had to do it in two steps; one for the milk and then one for the bottle. It worked well for us.