It depends on some factors and needs, but generally, members of your household, friends that you borrow your car with your consents are covered by your personal insurance policy. Contact your car insurance broker or agent to know who they treat as personal as it may varies from one vehicle insurance company to other. Some will treat it as only your household while others may allow relatives.
Another document to check it out is in your car insurance policy summary or policy booklet as some vehicle insurance company calls it. It will stress who is covered in your policy.
However, regardless of who is covered or not covered in your your car insurance policy, use this method now to get cheapest auto insurance.