Astrologers often disagree about parental assignments related to the 4th House. Some insist that the mother belongs in the 4th, others that the father belongs there. Many of the classical texts refer to the 4th as the house of the native’s “fathers” or progenitors, meaning both parents.
Recently I noticed a passage in Abu Ma’Shar that may shed some light on this dilemma. In Ben Dykes’ translation of Ma’Shar’s 10th century text On the Revolutions of the Years of Nativities (2019) the following comment appears on page 429 regarding the “lord of the orb,” a concept I’ve been using for a few years since reading about it in a 15th century text by Diego de Torres:
“And if the ‘lord of the hour of the house of fathers’ was made fortunate in a male sign, the condition of the father will be bad; and if it was in a female sign, the condition of the mother will be bad.” — Abu Ma’Shar
Clearly, Abu Ma’Shar assigns both parents to the 4th “house of fathers” and interprets their fate in a given year by whether the lord of the orb of the 4th house is made fortunate in the Solar Return for that year. Which of the two parents will be affected by the afflicted status depends on whether the lord of the orb of the 4th in a particular year falls in a masculine or feminine sign. An afflicted lord of the orb of the 4th house falling in a masculine sign means that the native’s father will suffer ill fortune but if in a feminine sign, the mother is the one who will be affected.
It appears that at its most fundamental level the 4th house has been traditionally assigned to both parents. Later developments in astrology led to giving only one of the two parents to the 4th house and placing the partner of that parent (the co-progenitor) elsewhere.