Must child be present to bill 90801

Can a provider routinely bill for a 90801 when the initial interview is with the parents only. Provider of service is a LCSW or PHD. Does the age of child make a difference?

re: Must child be present to bill 90801

http://www.mnpsychsoc.org/MA.pdf
CPT® also says: Psychiatric diagnostic interview examination includes a history, MENTAL STATUS, and DISPOSITION, and may include communications with family or other sources, ordering and medical interpretation of laboratory or other medical diagnostic studies.

I can't see how you can bill for an examination of the patient if the patient is not there? Not my field though so someone else may have a different answer.