We use nuk bottles and I bought the sippy cup which is just a different nipple with a sippy type of spout which is soft period I thought she would love it because she likes to chew on the nipples of her bottle. I put water in it a few months ago and she didn't want it so I decided to throw some milk in it today and she does not want it still. Put the milk in her regular bottle and she was just fine period I also use a 360 cup but she really doesn't want to use that unless the cap is off. I've also tried hard plastic sippy cups and she doesn't want those either. Any suggestions? She is almost 13 months