A family member of the former "Survivor" producer suspected of killing his wife in Mexico has made a legal move to gain temporary guardianship of the couple's two children.

In documents filed today in L.A. Superior Court and obtained by TMZ, Carla Burgos Van Bastelaar, claims she is the sister of the murdered woman, Monica Burgos Beresford-Redman.

In the documents, Carla states, "The mother of the children, Monica Burgos Beresford-Redman, was found murdered in Cancun, Mexico ... Their father, Bruce Beresford-Redman, has been arrested on suspicion of murdering her."

Carla also states, "I am the nearest blood relative of their mother, as I am her sister."

Beresford-Redman was released from custody early Friday morning because investigators didn't have enough evidence to hold him.

UPDATE 9:02 PM ET -- Looks like the sister was too late. A judge has granted temporary custody to the children's grandparents. It is believed it was Bruce Beresford-Redman's parents who were given custody.