The actress, model and designer, who is also Joaquin Phoenix‘s little sister, is asking for joint physical and legal custody of their children — sons Indiana, 12, and Atticus, 9 — as well as spousal support, according to court documents obtained by PEOPLE on Monday.
The couple separated in November 2015 after nearly 10 years of marriage and 16 years together. They announced their split publicly last March.
“Casey Affleck and Summer Phoenix have amicably separated. They remain very close friends,” the Oscar winner’s rep told PEOPLE in a statement at the time.
Affleck, 40, and Phoenix, 37, began dating in 2000, and after six years together and the birth of their first son, they wed in June 2006. They were last seen at a public event together in 2014.