Review on Infantino Textured Multi Ball Set by Justin Rasmussen

I'm torn. Pros: My daughter loves them so much and is fascinated by each one. She also enjoys learning to throw and catch. And she makes the funniest grimaces when I rub her legs or arms. Cons: Mold! She chews it constantly, causing saliva to collect in it. We had to throw the ball away as it was moldy on the inside and she only wore it for about 6-7 weeks. Is there a way to soften them without an air hole? Interestingly, we've only noticed mold in one room so far, and this is the green one others showed with mold. We still have the rest and will be keeping an eye on them, but this is clearly an annoyance and a clear design flaw here.