I would be more concerned with my broody being not that great than anything, in that situation... are other hens piling in with her and crushing babies, maybe, if she’s sleeping in the nest with her chicks? I could see duck hens crushing/losing babies, yes, they’re not the most attentive mamas, but my silkie is a stellar mom already. No chick left behind and if one is straggling she waits for it or brings everyone else back to collect it. And no way anyone else would ever even think of touching one of her babies, not if they want to keep their eyes in their heads... she still lets her 10 week old chicks sit with/under her, and welcomes the 14 week old silkie as well. The more the merrier.