CAL. FAM. CODE § 6550 : California Code - Section 6550

(a) A caregiver's authorization affidavit that meets the requirements of this part authorizes a caregiver 18 years of age or older who completes items 1 to 4, inclusive, of the affidavit provided in Section 6552 and signs the affidavit to enroll a minor in school and consent to school-related medical care on behalf of the minor. A caregiver who is a relative and who completes items 1 to 8, inclusive, of the affidavit provided in Section 6552 and signs the affidavit shall have the same rights to authorize medical care and dental care for the minor that are given to guardians under Section 2353 of the Probate Code. The medical care authorized by this caregiver who is a relative may include mental health treatment subject to the limitations of Section 2356 of the Probate Code.

(b) The decision of a caregiver to consent to or to refuse medical or dental care for a minor shall be superseded by any contravening decision of the parent or other person having legal custody of the minor, provided the decision of the parent or other person having legal custody of the minor does not jeopardize the life, health, or safety of the minor.

(c) A person who acts in good faith reliance on a caregiver's authorization affidavit to provide medical or dental care, without actual knowledge of facts contrary to those stated on the affidavit, is not subject to criminal liability or to civil liability to any person, and is not subject to professional disciplinary action, for that reliance if the applicable portions of the affidavit are completed. This subdivision applies even if medical or dental care is provided to a minor in contravention of the wishes of the parent or other person having legal custody of the minor as long as the person providing the medical or dental care has no actual knowledge of the wishes of the parent or other person having legal custody of the minor.

(d) A person who relies on the affidavit has no obligation to make any further inquiry or investigation.

(e) Nothing in this section relieves any individual from liability for violations of other provisions of law.

(f) If the minor stops living with the caregiver, the caregiver shall notify any school, health care provider, or health care service plan that has been given the affidavit. The affidavit is invalid after the school, health care provider, or health care service plan receives notice that the minor is no longer living with the caregiver.

(g) A caregiver's authorization affidavit shall be invalid, unless it substantially contains, in not less than 10-point boldface type or a reasonable equivalent thereof, the warning statement beginning with the word "warning" specified in Section 6552. The warning statement shall be enclosed in a box with 3-point rule lines.

(h) For purposes of this part, the following terms have the following meanings:

(1) "Person" includes an individual, corporation, partnership, association, the state, or any city, county, city and county, or other public entity or governmental subdivision or agency, or any other legal entity.

(2) "Relative" means a spouse, parent, stepparent, brother, sister, stepbrother, stepsister, half brother, half sister, uncle, aunt, niece, nephew, first cousin, or any person denoted by the prefix "grand" or "great," or the spouse of any of the persons specified in this definition, even after the marriage has been terminated by death or dissolution.

(3) "School-related medical care" means medical care that is required by state or local governmental authority as a condition for school enrollment, including immunizations, physical examinations, and medical examinations conducted in schools for pupils.