Quote from Rachel in The One with Rachel's Sister
Phoebe: It's just, I was- I was with Ross and Jill after you left, and I'm pretty sure I saw a little spark between them. Rachel: What? Phoebe: Yeah, I mean, it's probably nothing. But I just wanted to warn you that there might be something there. Rachel: With Ross and Jill? Phoebe: Yeah. Rachel: With Ross and my sister? Phoebe: Yeah. Rachel: With my sister Jill and my ex-boyfriend Ross?