Before we get very far into this, I want to acknowledge a point that you might be thinking right now: "But MegaBearsFan, Yorshka tells us who her parents are!" Or at least, she tells us that her father is Gwyn and her sister is Gwynevere and her "brother" is Gwyndolin. Seems pretty cut-and-dry right? OK, blog post over. If I keep writing on topics like this, I'm going to become very prolific!
... Well, maybe it's not quite that simple. This all seems rather fishy, and I'm not so sure if I'm willing to take Yorshka's words at face value. We still have the Ringed City DLC coming out for Dark Souls III at the end of this month, so it's entirely possible that DLC will settle the questions raised in this post. But until then, please humor me as I take a dive down a bit of a rabbit hole.
Yorshka directly states that Dark Sun Gwyndolin is her brother.
Before we go any further, let's take a look at what Yorshka actually says - her full dialogue can be conveniently read on fextralife (among other Souls wikis). When you meet Yorshka and perform the Darkmoon loyalty, she mentions:
"If thou shalt swear by the Covenant, to become a shadow of Father Gwyn and Sister Gwynevere,
A blade that shall hunt the foes of our lords;
Then I place thee under the aegis, and the power, of the Darkmoon."
If you level up in the covenant, she'll go on to talk about her relation to Dark Sun Gwyndolin:
"The Darkmoon Knights were once led by my elder brother, the Dark Sun Gwyndolin.
But he was stricken by illness, and leadership of the knights fell to me.
Then Sulyvahn wrongfully proclaimed himself Pontiff, and took me prisoner.
Oh where could my dear brother be?"
If you take this all at face value, then it seems pretty cut-and-dry, but take another look at the actual subtitle text. When she talks about Gwyn and Gwynevere, she uses the words "Father" and "Sister" (respectively), implying that Yorshka may be the daughter of Gwyn and blood sister to both Gwynevere and Gwyndolin. However, notice that, unlike when speaking of her brother, the words "Father" and "Sister" are capitalized, as if they are proper nouns or - more likely - titles... [More]