Very good advice!Brooding really takes a toll on a hen. Yours has had barely a break from this arduous task, and I wonder if she hadn't fully recovered her health and vigor from the last time before she went broody again.
Part of being broody is loss of appetite, so she may be just worn down and needs building back up nutritionally. You have a decision to make. Do you wish for her to finish rearing these chicks or do you want her to focus on getting strong again?
Since she isn't going to want to eat as she should to regain strength as long as she has this job to do, you may want to take the chicks away and let the other hen take over or just brood them yourself.
Then she needs to have her hormones broken by a stint in a broody cage where you can begin feeding her special high protein food and Poultry Nutri-drench to build her up. She needs to be separated visually and audibly from the chicks or it can keep the hormones going having the chicks around during this breaking process. (a few days.)
It could be something much more serious such as a reproductive issue, but I'm going for the most likely cause given her history of being a serial broody.