Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Great design; poor function

We purchased this to dispense gripe water to our newborn son. It works extremely well in administering the liquid to him as he has no problem accepting the pacifier or sucking out the medicine, which we use daily. Unfortunately, the dispenser began leaking shortly after we started using the plunger portion. Perhaps our item is defective, but the leaking renders it extremely messy (and the gripe water is sticky) and we will be buying a replacement, after owning this for only six weeks.