Joaquin Phoenix is arguably another powerhouse of Hollywood, ranked among the greats. His ability to play a tortured yet breathtaking Joker is just one indication that Phoenix is all about embracing dark and challenging roles.

In real life, though? Joaquin really tries to do what's right and doesn't shy away from tough stuff. He was close to his brother River, whose death still affects the actor to this day.

And he's been vegan since childhood, taking pity on all animals suffering a cruel fate to wind up on folks' plates. In fact, thanks to one Oscars speech, Phoenix even convinced Lena Dunham to go veggie.

While he's known as a bit of a black sheep in Hollywood, there is a reason why Joaquin Phoenix is still a household name and Casey Affleck has fallen off the charts.

The two first met in 1995, while filming 'To Die For', and became close friends. They were roommates in New York, got tattoos in Italy, and were soon tied together in ways other than their time as roommates and costars.

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First, Casey Affleck married Joaquin's younger sister, Summer. Yep, Joaquin Phoenix and Ben Affleck were sorta family at one point! Summer Phoenix and Casey Affleck were married in 2006 and divorced in 2017.

But on the set of 'I'm Still Here' in 2010, which Joaquin acted in and Casey directed, the two were still pretty close. Casey was basically Joaquin's best friend at that point.

The events on set wound up being the reason why Joaquin and Casey became less than friends, though.

In fact, in one revealing interview with Vanity FairJoaquin admitted that he hadn't spoken to Casey in years. Why? Because 2010's 'I'm Still Here' resulted in accusations from two women on the film's crew that Joaquin and Casey had acted inappropriately while on location for the movie.

A lawsuit claimed that Casey and Joaquin used their hotel room for illicit activities with two women, and also that some movie scenes were created solely for Affleck's "gratification" and not in the creative direction of the film. Those scenes didn't make it into the film, hence the two plaintiffs' perceptions that Casey was acting in his own interests rather than pursuing a creative angle.

After all that, Vanity Fair noted, Joaquin's lawyers told him not to discuss the allegations against Casey. The same year, Casey settled the suits, but the damage was already done.

The former friends seemed to have a falling out at that point, with Casey later divorcing Joaquin's sister. In a later interview, Joaquin confessed that he regretted not "having been more vocal about abuses of power he witnessed in the past," said Vanity Fair, and though he pointed out that he wasn't speaking specifically about Casey's legal problems.

Still, fans can assume that Joaquin took both his sister's side in the divorce, and the victims' side in the lawsuit against his former friend.

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