A designated provider (caregiver) is a person who is aged 21 years or older who has been approved by a qualified patient and allowed by the patient's medical practitioner to purchase, supply, or cultivate marijuana (cannabis) for the patient. If the qualified patient is younger than 18 years of age, then the designated provider (caregiver) must be a parent or guardian. A designated provider (caregiver) can only serve one patient at any one time.