Cal. Lab. Code § 3503

No person is a dependent of any deceased employee unless in good faith a member of the family or household of the employee, or unless the person bears to the employee the relation of spouse, child, posthumous child, adopted child or stepchild, grandchild, father or mother, father-in-law or mother-in-law, grandfather or grandmother, brother or sister, uncle or aunt, brother-in-law or sister-in-law, or nephew or niece.