You can't use CAS to add sims to an existing household. You would have to place them in a household of their own first and then combine/merge them with the original household through Edit Town or by using MasterController's Add Sim once they are already in town someplace. Is this what you tried to do?
Not sure what you meant by the pets didn't follow. They may have still been physically standing on the residential lot where they were placed, but they should have been controllable if you added them to your own active household. In the case of pets only, a placeholder sim to act as temporary head of household would also have to be created for placement purposes.
PortraitPanel doesn't add sims to households, it only adds them to the panel.