Agree with all the others but also curious what you mean by dual purpose versus family pet birds? Both BOs and SLWs are considered dual purpose breeds and are a similar size so do well together. And BOs are very friendly and can be "pets", mine are, but they're still dual purpose birds. Maybe she just means SLW are more ornamental color or whatever or that they will cross breed? Either way it shouldn't matter too much. If you want pure birds just separate them like others said. But they shouldn't have any problems being together. Although that said sometimes Wyandottes can be bossy but not usually in a mean way and so can any bird so just keep an eye on them.
Also, all that said, there can sometimes be problems with heavier dual purpose breeds and lighter/smaller breeds of birds. And I especially would never recommend mixing bantams (including silkies) with the heavier dual purpose breeds and they are smaller and gentler and can be picked on even by friendly breeds like BOs.
But yeah they should all be fine.
Right now I have 1 Barred Rock, 2 Black Australorps, 3 Buff Orpingtons, and 2 Easter Eggers and they all get along well. I'm adding 1 Golden Laced Wyandotte (GLW), 1 Silver Laced Wyandotte (SLW), 1 Speckled Sussex, 1 Partridge Rock, and 1 free chick, don't know what it's gonna be yet, in October and I think they'll all do fine.
Good luck!!!