Ross: (angrily) I thought you were my best friend--this is my sister! My best friend and my sister! I cannot believe this!
Chandler: Look we're not just messing around... I love her. Okay? I'm in love with her.
Monica: I'm so sorry that you had to find out this way, but it's true... I love him, too.
Ross: (after it sinks in, joyously) My best friend and my sister! I cannot believe it!