well, it is odd, cuz she was such a great broody hen and mom, I'll keep watching her,, maybe she is pushing them away now that they are almost 5 weeksThat's a weird problem if they have plenty of protein.
Ive never had issues with a hen past the first couple days. I also never let them have chicks again if I had issues. I always have a broody silkie or six so I can just take the babies and give them to a good mom. I've only had issues with some large fowl breeds or EEs with only a little silkie blood.