Lisa Marie Simpson, voiced by Yeardley Smith, is Homer and Marge's oldest duaghter and the middle child on The Simpsons.  Lisa is very intelligent, plays the saxophone, is a vegetarian, Buddhist, and definitely a bit of a young political activist.  She's basically the complete opposite of her brother, Bart.

Lisa Simpson Quotes

Lincoln, Lincoln. I've been thinkin'. What the hell have you've been drinkin'? Is it water? Is it wine? Oh, my gosh. It's turpentine!

Bart & Lisa

Look, Dad, I made fish sticks. They're burned on the outside, but they're frozen on the inside, so it balances out.

Lisa

The Simpsons Quotes

Sir, I got carsick in your office.

Ralph

Mr. Burns: (reading Homer's letter) "Dear Mr. Burns. I'm so glad you enjoyed my son's blood, and your card was just great." Why Simpson, you've made my day, you're a true gentlemen.
Homer: Well I-
Mr. Burns: Hello, there's more. (continues reading) "In case you can't tell, I'm being sarcastic. You stink! You are a senile bucktoothed old mummy with bony girl arms and you smell like an elephant's butt!"