For months I had been fretting over cups. Seriously. I loved the simplicity of the plastic straw cups for my kids. But I was worried about BPA. I didn't want to poison my kids...but every drinking cup available locally was plastic. UGH!
Then I found this.
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Man, I love this thing! It is stainless, spillproof, and maintains temperature for 12 hours. They even have blue for my son and pink for my daughter, no more fighting over drinks!
For babies they have a sippy cup. These are available at mainstream super stores and online.
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Buy one.