I'm unsure how to proceed with billing the following service, I am in need of assistance-please!

Primary physician admitted patient to inpatient status for addison's crisis in the morning. The Hospitalist sees the patient that evening/night for addison's crisis. The hospitalist was not consulted by the primary care doc, but instead contacted by hospital staff regarding patient's condition. Both the PCP and Hospitalist are biling under the same tax ID. Are both services billable? If so, the PCP bills and Inpatient Admit, what would the Hospitalist bill?