Olivia de Havilland versus Joan Fontaine: sisters who hate each other since they were little
First assault. The rivalry between the two sisters for their parents' attention led Olivia to break Joan's clavicle during a childish fight, humiliate her in the school newspaper (in a fictional will, she bequeathed to her sister "the ability to earn children's hearts, something she doesn't have today") and to turn her back when Joan came up to congratulate her on her Oscar.
And that Olivia, indirectly, owed her first character of dramatic substance to her sister: when Joan was rejected for the role of Melania in Gone with the Wind, she told the director "I'm too elegant for the role? Then call my sister."
Second round. "Olivia always says that I have to be first in everything," Joan explained to People. “I got married before. I won an Oscar before. I had a son before. If I die before she does, she'll be furious because I even had to do that first." Precisely a death, that of her mother, put a definitive end to the sisters' relationship: Olivia did not invite Joan to her funeral or consult her about the decision to cremate her. Joan even stopped talking to her own daughter when she found out that she had a relationship with her aunt Olivia.
Joan fulfilled her own prophecy and died first, in 2013, while Olivia survives as the penultimate living legend (alongside Kirk Douglas) of golden Hollywood. She has finally won her sister over to something, although technically Joan was right: Olivia will be second only to her in death.
Shannen Doherty vs. Jennie Garth: Fight in 'Feeling' and beyond
First assault. The audience of Sensación de Vivir hated Brenda so much, considered a tomboy, that she took it on with her actress Shannen Doherty. She reacted by giving the world real reasons to criticize her: lateness on set, high-handedness with the crew, and late-night partying that ended up slapping anyone who got in her way. On one occasion, she got into a fight (punching or scratching, according to sources) with Jennie Garth, Kelly's interpreter.
Second round. The tension between Doherty and the rest of the world became so untenable that producer Aaron Spelling fired her after the fourth season. Years later she gave him a second chance on Charmed, but by the end of the third season, she too was dispatched killing off her character out of shot. The entire crew of the series had a party with the banner quoting the song from The Wizard of Oz: "Ding dong, the witch is dead."
In 2016, Jennie Garth cheered Shannen Doherty on when she was diagnosed with cancer with an Instagram photo of a “fight like Brenda” sticker next to a pink bow. The actress ended up overcoming the disease: neither Brenda nor Shannon had ever given up on anything, so they weren't going to start now.
Bette Davis versus Joan Crawford: Hate Is This
First assault. Bette Davis fell in love with Franchot Tone, her partner in Dangerous (1935), and Joan Crawford became engaged to him during filming. “I have never forgiven her and I never will,” Davis declared 50 years later, “she coldly, deliberately, and mercilessly stole it from me.” Crawford defended herself by clarifying that Tone admired Davis as an actress, but never saw her as "a woman". Since then her rivalry was cemented in that competition between the beauty of Crawford (more star) and the prestige of Davis (more actress).
Second round. Davis' mouth was off ("Joan has slept with every male Metro Goldwyn Mayer star except Lassie [the bitch]," "I wouldn't piss on her if she was on fire")), but when Crawford exploded it was more Arsonist: She put rocks in her pockets to make it harder for Davis to drag her into a scene from What Ever Happened to Baby Jane? (1962) and thus complicating her back problems, she made sure to collect the Oscar on behalf of Anne Bancroft for starring in the defeat of Davis (nominated that same year) and abandoned the filming of their next film together, Lullaby for a Corpse, after a week for fear that Davis would conspire against her again and steal the limelight.
As Hollywood's most legendary rivalry, it's hard to separate fact from mythology. Davis was going around saying that Crawford was S- attracted to her (Joan confessed to a close friend: "I wouldn't mind giving him a pipe if he caught me in the good mood"). It is also not confirmed that Davis actually uttered the phrase that ended their rivalry (on the day of Crawford's death: "You should never speak ill of the dead, only well... Joan Crawford is dead. Good"), but it is part of the show And that is something that both of them were phenomenal at.