#marque cain

Good question! Initially during the Batgirl 2000 run Cass finds out that Cain tried his cruel experiments on other kids before he had Cass, which makes sense. Then in her painfully badly written evil arc she suddenly decided that him having other kids was a huge betrayal that she hated him for and she started killing them. They may have mentioned in that arc that some of the kids were younger but I'm not reading that shit again to check 😭 so I'm just going to assume Cass was the youngest because it makes the most sense, even if some of the resentment indicates that he might have been raising them alongside Cass. Even Cain's newest trainees in Batgirl 2008 don't look any older or younger than Cass. Marque looks... around the same age as Cass and says that Cain stole her older than the other girls. But Cass does act older than her in some ways.

So honestly she could be older or younger. I personally prefer her older, because Cass being the youngest makes the most sense to me, even though she's clearly more experienced and mature than Cain's other kids. The writing was patchy at best for the whole arc so I do think you can just go with whatever option you prefer.