So, the two girls were brothers?
No, their baby daddies were. They’re paternal twins.
“fraternal” is the term that is used and has been used for eons by doctors and the world in general for twins, including girls, who are not identical. There are two varieties of twin, “identical” and “fraternal,” having to do with the fertilization of one or two eggs.
My comment was to another FReeper perhaps having a momentary lapse, who referred to them as ‘paternal.’ There’s no such thing as ‘paternal’ twins.