Lilly's catalogue of the sixth house names uncles and aunts on the father's side directly, and turning the chart from the fourth produces the same answer independently, but which of the two came first is not established here. The step may be a Hellenistic inheritance, an Arabic development, or a Latin systematisation, and the atlas has found no study that settles it. The answer matters because every derived reading of an extended relative inherits whatever assignment the parent's house is given.
What would resolve this A textual comparison across the Hellenistic, Arabic and Latin house literature, identifying the earliest passage that derives a collateral relative from a parent house rather than simply listing that relative among a house catalogue, and dating the transmission of that step.
OpenHistory of astrology; Arabic and Latin manuscript studies; history of the exact sciencesJames Herschel Holden, A History of Horoscopic Astrology