K.S.
I have a son thatis 13 months and I just went thru the samething...mine was taking sippy cups great but his iron had been low so what I did was switched to the NextStep Formula by Infanmil and my doc said it was basically powerded milk with allot more iron in it and I started mixing 1-2 ounces of whole milk with it and he is doing great! He is off the bottles and takes 2-3 ounces of formula with the milk and when he is 15 mo they will check his iron and if it is back to normal then I will gradually stop the formula but it is good for them until they are 24 months...hope this helps you! K.