If you want to play with her maturing into her powers, you're welcome to have the first few undead who fall into her thrall seem to oppose it and her, or perhaps try to escape her — while later undead are increasingly more obedient! Or they can heed her, but seem grudging as they do so, or perhaps verbally mutter, mumble and criticise her, while they obey her all the same. Or they can be perfectly docile - really, whatever makes it more fun!