"Lena Dunham, who I think is again terrific, how can she wear dresses above the knee?" Rivers asked Stern.
"I think the thing we love about her is she doesn't give a s--t," Stern, who previously had his own beef with Dunham, defended her. "Do you watch Girls? Do you watch when she's naked on there? She did a whole episode in a bikini, it was the funniest f--king thing I've ever seen."
Stern's co-anchor Robin Quivers chimed in, "And it think that's what she's going for: Just because I don't look like a bikini girl, I want a bikini."
"But that's wrong," Rivers replied. "You're sending a message out to people saying it's OK, stay fat, get diabetes, everybody die. Lose your fingers."
Stern said, "And she makes us laugh." "And I love her for that," Rivers replied.
In the end, Rivers admitted, "I love that she's funny, I love that she did well...but don't let them laugh at you physically."
"If you look the way you look, Lena, and that's fine and you're funny, don't say it's OK that other girls can look like this," she said, adding with a laugh, "Try to look better."