Among RFID authentication protocols, HB and its variants have received widespread attention due to their strength based on the underlying LPN problem. Several variations of HB exists in extant literature, each improving on previously proposed protocols. We use the iterative nature of the HB-family of protocols to develop a means to identify the presence of an RFID tag with the knowledge of the presence of a related RFID tag. Specifically, we use a fuzzy system to accomplish this through appropriate membership value assignments. We consider a supply chain environment where two or more RFID-tagged entities have some relationship in terms of their simultaneous presence in the field of the reader.