If I were you, since you've already put Mama in a relatively safe spot for the time being, keep an eye on everyone, but leave her & eggs alone for now. The aggression of the other birds may be from being confined and if at all possible, let them out even if only for an hour or two before roost...
Personally, I like Orpingtons but any breed can be gentled by early handling. It is normal to establish pecking order sometimes on a daily basis and can be seen as aggression. Only a problem when it gets bloody. Birds can get aggressive when they feel threatened.
Since you already raise layers, meaties aren't much different. Babies need Chick starter, then Grower/Finisher instead of Layer feed. Water should always be available 24/7.
CX are a hybrid to grow plumper faster and that is what causes a lot of the health & leg problems. Too much, too soon in...