[Uri’el-2012]

Koine doesn’t have the vocabulary for the distinction you make to be present in the original text. Brothers, stepbrothers and even cousinss are indifferently referred to as adelphoi in Greek throughout the Septuagint

How do you explain GSN-4773

4773 suggenh,j suggenes {soong-ghen-ace'}
Meaning: 1) of the same kin, akin to, related by blood
2) in a wider sense, of the same race, a fellow countryman
Origin: from 4862 and 1085; TDNT - 7:736,1097; adj
Usage: AV - kinsman 7, cousin 2, kinsfolk 2, kin 1; 12

<4773b> suggeni,j suggenis
Meaning: a kinswoman
Origin: fem. from 4773a
Usage: relative(1).
Notes: (1) Lit this is the sixth month to her who

[Philo-Junius]

But the New Testament is not part of the Septuagint, nor were St. Elizabeth and the Blessed Virgin brothers.

[Quix]

Thanks. I knew someone could do much better than I on that score.

However, I assume you are NOT UNDERestimating the capacity of a number of RC’s to argue with a fence post; employ daffynitions and otherwise shuck and jive; slip and slide; run and hide in running from the truth.