It's common for integration drama (nippy, chasing, etc.) just be patient. As long as no one is getting penned down and bleeding I leave it alone. Pullets can squeal and squawk like they are being killed even when just looked at LOLThat's good to know. What I didn't clarify is that the 3 pullets that are from their mother--were from me hatching their incubated eggsthe 3 hens don't even know the pullets are theirs--in fact, they're not integrating well... Our 1 lead hen is relentless at the 3 pullets (specifically around food). She's then influenced the other 2 to be nippy and mean to the pullets.
If possible, add another feed and water station (more feeders if possible). Having plenty of room for them to get away from older hens would be good - perches in the run gets them up and out of the way. Usually they will eventually work it out though.