Parent A has obtained full custody through the family courts of western Australia whilst on bail, pending trial is at risk of imprisonment. Parent A wants grandparent that they and the children are currently living with to having guardianship if imprisoned, Parent A was advised that because they have full custody they can make this decision, especially as the children are currently living with that grandparent. Is there a legal document that can be filled out to state this guardianship in preparation for the possible future?