False Colors, page 188:

“Ah, Bondarevsky, maybe you missed the significance of Murragh's full name,” Graham said, stepping into the awkward silence. “The dai Nokhtak hrai is a distaff branch of the Imperial Family. Murragh here is a distant cousin of the Prince Thrakhath's… maybe the last one alive. His grandmother was sister to the late Emperor. That makes him a legitimate heir to the Kilrathi throne.”