Note 034
From Chapter 25 of the Decline & Fall

The uncertain degree of alliance or consanguinity, is expressed by the words

Ancient Greek cognatus, consobrinus (see Valesius ad Ammian, xxiii 3).

The mother of Procopius might be a sister of Basilina and Count Julian, the mother and uncle of the Apostate. Ducange, Fam. Byzantin. p. 49.