We've finally gotten to the bottom of the Joan Rivers and Miss Piggy feud.
As you know, the Fashion Police queen ended up falling into a cake on Friday at the QVC Red Carpet event when she and Miss Piggy got into explosive scuffle.
It turns out the two were besties back in the '70s, but things soured when Piggy was cast over Joan in The Muppet Show, according to Behind the Feud, a new documentary exclusively released to E! News.
"Tupac and Biggie, Stalin and Trotsky, Diane Sawyer and Grumpy Cat, this was bigger than all of those," says Sarah Silverman, who appears in Behind the Feud along with Jane Lynch, Gene Simmons and Melissa Rivers.
They seemed to have smoothed things over in 1984 when Piggy invited Joan to make a cameo in The Muppets Take Manhattan. "When the director yelled, 'Action,' all that baggage just seemed to melt away," Joan says. "It was nice."
Kermit the Frog gushed, "It was show business magic."
But then the friendship imploded again when jealousies ran wild during the filming of sci-fi movie for director Garry Marshall.
They hadn't seen each other since—until Friday's disastrous run-in, that is.
"[Joan] called me crying from her car," Silverman said. "She had gotten cake all over her wig, all over her face face, which is the face she wears over her face."
Gabourey Sidibe also appears in the documentary. "When I saw that cake thing, it just broke my heart."
We can't wait to see what happens when Miss Piggy appears with Joan on QVC on March 16 just days before Disney's Muppets Most Wanted hits theaters on March 21.
Piggy's Muppets Most Wanted co-star Ricky Gervais will be on E! News tomorrow—tune in at 7 p.m. and 11:30 p.m.