Are the daughters of paternal uncles and aunts, and maternal uncles and aunts, forbidden due to marriage affinity?
Chapter on What is Prohibited to Marry and Combining Between Them and Other Matters
Al-Mughni
Book of Marriage
Primary text
The daughters of paternal aunts and maternal aunts are lawful to marry. This is established by the consensus because they are explicitly mentioned as lawful for the Prophet, peace be upon him, in the verse: "O Prophet, We have made lawful to you your wives... and the daughters of your paternal uncles and the daughters of your paternal aunts and the daughters of your maternal uncles and the daughters of your maternal aunts" (Quran 33:50). They are not mentioned among the permanently prohibited women, thus falling under the general permissibility: "And lawful to you are all those beyond these" (Quran 4:24). Likewise, the daughters of the wives of fathers and sons are lawful because the prohibition applies to the wives themselves as 'halā'il' (formerly married to the father/son), and this prohibition does not extend to their daughters, nor is there any other reason necessitating their prohibition, thus they are included in what is lawful according to the verse (Quran 4:24).
Supporting text
Every woman whose mother is permanently forbidden renders her daughter forbidden because the mother's prohibition transfers to the daughter (as the daughter becomes a sister, aunt, or maternal aunt). The daughters of sisters and their daughters are forbidden because they are daughters of a sister, as are the daughters of a brother's daughters, except for the daughters of paternal and maternal aunts, who are lawful by explicit text.