Penny: Come on, it'll be fun, and, you know, your mom was genuinely hurt we didn't invite her to the first one.
Leonard: Look, in our defense, it was kind of a spur of the moment thing, and also, we don't like her.
Penny: Leonard, come on, she's your mom. If we can do something to make her happy, why wouldn't we?
Leonard: I just said why, we don't like her.