ET reports that Phoenix cited "irreconcilable differences" in the petition filed Monday with the Superior Court of California in Los Angeles.
According to People magazine, the actress, model, designer, and younger sister of Joaquin Phoenix filed court documents seeking spousal support and joint physical and legal custody of their children, sons IN, 13, and Atticus, 9.
The couple, who tied the knot in 2006, legally separated in November 2015, after being together for over 16 years.
They have asked for joint legal and physical custody of their three young children: Violet, 11, Seraphina, eight, and five-year-old Samuel.
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Casey told the publication that Summer 'was going out with someone else [at the time] and [he told Joaquin], "Man, she's cute"'.
The little brother of Ben Affleck and Summer Phoenix are separating for good...
So, this means that both Casey and Summer are single now. They subsequently announced their split in March 2016. The two separated after more than 13 years together.
Apparently, the split has been amicable, as a representative for Casey claimed that the two stars have remained close friends.
Remains that this divorce marks the end of a very nice couple.