James Cameron and Wife Suzy Amis Petition to Become Permanent Guardians of Daughter's Friend

James Cameron and his wife Suzy Amis Cameron are petitioning to become the permanent guardians of one of their daughter's friends.

On Oct. 6, the couple requested permanent custody of the 16-year-old girl they welcomed into their home after she befriended one of their three daughters, according to court documents obtained by PEOPLE.

The two now have the power to travel with the teenager internationally alongside their other children and to reside outside the state of California or outside of the United States if they wish it.

Cameron has been hard at work directing the upcoming Avatar sequels in New Zealand.

In May, the couple filed a petition to become the temporary guardians of the teenager, according to court documents obtained by PEOPLE at the time. They were granted temporary guardianship in June.

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The Avatar director said the teenage girl lived with her biological parents in New York until September 2019. The girl's parents became "increasingly unable to care" for her, the Camerons claimed in their petition.

The couple's daughter and the teenager "maintained a close friendship, connecting online daily and even visiting each other in their respective hometowns," according to the couple.

The teenager has been living with the Cameron family at their California home and has been going to school in the state since September 2019.

They say the teen girl is now "thriving" under their care and that "she wishes to continue to be cared for" by the couple with the permission of her parents and grandparents.

The director shares three children with Amis Cameron: daughters Claire, 19; Quinn, 17; and Elizabeth 13. He also has a 27-year-old daughter, Josephine, from his marriage to Terminator star Linda Hamilton. Amis Cameron has a son, Jasper, 30, from her previous marriage to actor Sam Robards.