Sippy cups can be difficult (and frustrating) for baby to use, mostly due to the stopper, which prevents spillage.
When starting out with the sippy cup, remove the stopper so that liquids flow easily. Once baby drinks from the sippy cup by about 9 months of age, switch to a straw cup, which will strengthen oral and speech development. Prolonged sippy cup usage may cause a child to thrust his tongue forward when swallowing, which can interfere with acquiring speech and the ability to chew and swallow different food textures. A straw cup (particularly with a short straw), promotes proper tongue positioning and action, leading to effective swallowing patterns. In fact, the straw cup, more than an open top cup, strengthens oral motor skills for eating challenging foods like a chewy bagel or meat.