Earlier this morning, TMZ reported that Bynes' psychiatric hold had been extended for 30 days under doctors' orders, which requires the patient to be "gravely disabled as a result of a mental disorder."
Reiser said a mental health court has control over Bynes' medical treatment, but if she is released from a psychiatric facility then her mother will have authority to decide treatment.
The former star of Nickelodeon shows "All That" and her own variety series has been in a psychiatric hospital since last month. Authorities placed her in the hospital after she started a small fire in the driveway of a house in her hometown of Thousand Oaks, Calif.
Lynn Bynes will also have control over her daughter's finances.