Lab. Code, § 3501

(a) A child under the age of 18 years, or a child of any age found by any trier of fact, whether contractual, administrative, regulatory, or judicial, to be physically or mentally incapacitated from earning, shall be conclusively presumed to be wholly dependent for support upon a deceased employee-parent with whom that child is living at the time of injury resulting in death of the parent or for whose maintenance the parent was legally liable at the time of injury resulting in death of the parent.

(b) A spouse to whom a deceased employee is married at the time of death shall be conclusively presumed to be wholly dependent for support upon the deceased employee if the surviving spouse earned thirty thousand dollars ($30,000) or less in the twelve months immediately preceding the death.