Bests & Worsts Reviews from Amazon

My baby never, ever bit me while nursing. Then she started using this sippy cup. It was so difficult for her to get water out that she started biting and chewing on the end. I tested the cup out myself and the suction required to get liquid out is difficult, even for me as the adult. Soon, she started biting me while nursing. I immediately stopped giving her this sippy cup and now she doesn't bite me while nursing anymore. I'm not positive they are correlated, but it seems likely.