Sounds like Jeremy purposely knows how to get under your skin and get a reaction. I take it it's an older brother! It takes a lot of self training, and it's horrendously hard, but ignore with a smile (I prefer a smirk, personally) may do the trick. He knows he can rock your boat, but hold your balance and stay calm. It'll make you THE better person! Never belittle yourself to that level! EVER!