דברי הימים א, פרק ב׳, פסוק מ״ז

As the family history of Caleb unfolds, a new figure named Jahdai suddenly appears, accompanied by a detailed list of his six sons: Regem, Jotham, Geshan, Pelet, Ephah, and Shaaph. However, a noticeable gap exists in the record. Jahdai's own parentage is missing, leaving his exact connection to the broader family tree a mystery [ביאור שטיינזלץ].

To resolve this missing link, commentators trace Jahdai back to Caleb's concubine, Ephah, who features just prior in the family history. One perspective suggests that Jahdai is not a newly introduced individual at all. Rather, he is actually one of Ephah's previously listed sons who simply went by a second name [רד״ק, מצודת דוד].

Alternatively, another approach maintains that Jahdai is a distinct son of Ephah, completely separate from the brothers mentioned earlier. In this view, the direct connection between him and his mother is left unstated for a practical reason. Out of all of Ephah's children, only Jahdai produced a family line that required further detailing, making him the sole focus of the continuing lineage [רש״י].