I have the same problem so I had to build a set of small 4x4 broody pens to house the hens/chicks until the chicks are weaned enough (2-3 months) to go to the growout pen and the hens return to the main layer flock.
I've never had a hen actually kill a bity but they have flogged them to near death and caused serious injury. Even if there are no other momma hens/chickc around, my broodys still attack my other hens and they spend all day squaking each other, bouncing off the walls and knocking each other over causing stress & chaos.
And yes she will be that way until the chicks are weaned then she will return to normail until she hatches another batch of bittys.
I've only had this once, when my alpha hen and the omega hen brooded and hatched the same day. The alpha hen decided she was going to kill the omega hen's chicks. I pulled omega and her babies out and just let her raise them in another pen.
this was the only time I've had that problem. I've had hens raise clutches close in age and do fine. I had two hens co-brood the same eggs and they both raised the five chicks successfully.
I'd pull one of the hens and her babies out and raise them separate. You'll just have to watch this momma next time there's babies to see how she does. Perhaps a difference in age of the chicks will help, or maybe she'll always be aggressive toward other hen's chicks, really no way to know.