The male Castor clones (Ari Millen) bother the Leda clones’ (Tatiana Maslany) for much of Orphan Black’s new Season 3. Mostly, their presence is annoying for Sarah and her sisters, albeit dangerous to a point. Still, it seems like this has the potential to change now that one crucial fact has been unveiled: the Castor and Leda clones are siblings. Will this revelation change the way the Castor clones view Sarah and her sister clones? Might the siblings form an alliance later on this season?

Earlier it was intimated that Sarah would form some type of alliance (though quite brief) with Castor clone Mark, given that she saved his life from Gracie’s (Zoe De Grand Maison) Prolethean, rifle-wielding mother, Bonnie (Kristin Booth). This raises some interesting questions about Sarah: would she have saved Mark even if she hadn’t known that they were related?e related to the Castor clones? According to The Hollywood Reporter, Marisa Roffman points out that “while Sarah has fiercely embraced her new sisterhood, the discovery [of her being related to the Castor clones] will lead to her own mixed feelings on the matter.” Co-creator John Fawcett further stresses that “it certainly adds a massive layer of complexity for Sarah, especially.” This also brings a new outlook on the idea of family for Sarah, as she’s gone from being an orphan to discovering she is one of many siblings; albiet some she would prefer to be unrelated to.

Predictably, there is distrust and confusion between the related clones. It’s not like the Castor clones will be winning over Sarah and her sisters with their charm; it’s becoming difficult to count how many times they’ve held Sarah at gunpoint. Co-creator Graeme Manson notes the challenges of Leda and Castor clones uniting, as the Castor clones “have not acted like family to this point, and we’ll have to wait and see if they learn to.” As bad as the Castor clones may seem, though, there are always other enemies, for example, Dr. Coady (Kyra Harper), who manipulates the Castor boys and does not have their best interests at heart. If the Leda and Castor clones do form an alliance or simply call a truce, it will not be an easy adjustment. On the flip side, if the Castor and Leda clones remain at odds, it won’t be long before they realize that they’re all they have, and it might be easier together to avoid the corrupt corporations, religious groups, and abusers of science who prey on them.