Gilbert has to care for his brother Arnie and his obese mother, which gets in the way when love walks into his life.

Gilbert: [climbing of the water tower] It's not going to happen again. This is the last time. Right Arnie?
Arnie: It's the last time.
Gilbert: Okay. Let's go.
Arnie: But I want to go back up there again.
Arnie: I'm having a birthday party, but you're not invited, but you can come if you want.
Arnie: Match in the gas tank, *boom* *boom*!
Becky: Tell me what you want, as fast as it comes to you.
Gilbert: Uhh...
Becky: Okay?
Gilbert: 'Kay.
Becky: Okay. What do you want?
[He's thinking about it]
Becky: Faster!
Gilbert: Okay. I want a new thing. House. I want a new house. And a family.
[He sighs heavily]
Gilbert: I want Momma to take aerobics classes. I want Ellen to grow up. I want a new brain for Arnie. I want...
Becky: What do you want for you? Just for you?
Gilbert: I want to be a good person.
Momma: [meeting for the first time] Hello.
Becky: Hi.
Momma: I haven't always been like this.
Becky: Well, I haven't always been like this, either.
[Arnie jumps onto Gilbert's back]
Gilbert: God, Arnie, you're getting so big. Pretty soon I ain't gonna be able to carry you no more.
Arnie Grape: No, you're getting littler, Gilbert. You're getting littler, you're shrinking! You're shrinking, Gilbert, you're shrinking! Shrinking, shrinking, shrinking!
Becky: I love the sky. It's so limitless.
Gilbert: It is big. It's very big.
Becky: Big doesn't even sum it up, right? That word big is so small.
Momma: You're my knight in shimmering armor. Did you know that?
Gilbert: I think you mean shining.
Momma: No shimmering. You shimmer, and you glow.
Arnie Grape: Good night to you but not me.
Gilbert: Why will I take care of it?
Arnie: Gilbert...
Gilbert: Hmm?
Arnie: 'Cause you're Gilbert.
Gilbert: 'Cause I'm Gilbert.
Gilbert: [to Becky] I don't know what to say.
Arnie: Say "thank you," Gilbert. "Thank you."
Gilbert: [whispering] Thank you.
Gilbert: You know what? You're such a big boy.
Arnie: Yeah!
Gilbert: You're such a big boy.
Arnie: I'm a big boy!
Gilbert: You know what? I bet you could do this all by yourself if you really wanted to. Could you do this by yourself?
Arnie: I'm a big boy!
Gilbert: Yeah, you're a big boy. Now take this...
Arnie: Take this.
Gilbert: Wash everything, your towels are there.
Arnie: Okay!
Gilbert: And your robe is there.
Arnie: Okay! The big boy is gonna wash himself!
Gilbert: I'm not gonna let her be a joke.
Gilbert: You don't hurt Arnie, you just don't.
Tucker: How's momma?
Gilbert: She's fat.
Tucker: Come on, man. She's not all that big, Gilbert.
Gilbert: What?
Tucker: Listen, I saw a guy at the state fair who was... a little bit bigger.
Gilbert: A little bit bigger?
Tucker: Look, all I'm sayin' is that she's not the biggest I ever seen, okay?
Gilbert: Tucker, she's a whale!
Tucker: Well, take her out for a walk once in a while.
Gilbert: Take her out for a jog!
Arnie: She's a whale! Tucker, she's a whale!
Becky: It's okay,don worry about it.
Gilbert: no no I'm really... I'm really sorry
Becky: It's okay.
Gilbert: I'm really sorry.
Becky: Don't be sorry,Are you sorry?... no,I'm not sorry,he's not sorry,we're not sorry,don't be sorry.
Arnie: I'm not sorry
Gilbert: We don't really move. I mean, we'd like to, but... my mom is sort of attached to the house. Attached is, I guess, not the right word. She's pretty much wedged in.
Arnie: We're not going anywhere! We're not going anywhere!
Arnie: [looks at Gilbert in the truck] Where're you going?
Arnie Grape: I could go at any time.
Gilbert: Bobby, how's business?
Bobby: Oh, not good... nobody's dying.
Arnie: Dad's dead! Dad's dead! Dad's dead! Dad's dead! Dad's dead! Dad's dead!
Gilbert: I know a boy whose name is Arnie... he's, uh, 'bout to turn 18 and have a big party. I know a boy whose name is Arnie. C'mon down, buddy.
Gilbert: Did you ever see a beached whale on television?
Becky: Yeah.
Gilbert: Yeah. That's her. That's my mom.
Becky: [pauses] What about your dad?
Gilbert: Uh, some other day. Some other day.
Arnie Grape: I killed him Gilbert , I killed him!
Mr. Lamson: What's going on over there at "Food Land"?
Gilbert: [labeling price tags on cans] I wouldn't know, I don't shop there.
[puts a can up and looks at boss]
Gilbert: I'd rather die.
[smiles]
Gilbert: Ellen? Ellen?
Ellen Grape: What?
Gilbert: Could you not talk with your mouth full?
Ellen Grape: Excuse me?
Gilbert: You're making me sick, I'm gonna throw up.
Ellen Grape: Oh, okay, dad. Sure thing, dad.
Becky: Tell me what you want as fast as it comes to you.
Gilbert: I wanna be a good person.
[about his upcoming birthday party]
Arnie: Momma, I want hot dogs!
Momma: We're gonna have hot dogs, honey. I promise. We're gonna have hot dogs.
Arnie: Momma, I want hot dogs!
Momma: We're gonna have hot dogs.
Betty Carver: Hey. I could have had any guy, any guy, but I chose you. I chose you.
Gilbert: Why did you?
Betty Carver: [pause] Because... I knew you'd always be there. Because I knew you'd never leave.
Gilbert: I had a nice time tonight.
Becky: I know.
[smiles]
Arnie: [In the middle of Mr. Carver's funeral] Gilbert, it's the Burger Barn! It's the Burger Barn, Gilbert, the Burger Barn!
Becky: It's a praying mantis. Do you know how they mate? The male will sneak up on the female and she'll bite off his head and the rest of his body will keep on mating and when they're done... She'll eat him. She'll eat the rest of him.
Momma: You left, and I hate that. You know I hate that.