In the fifth season of Buffy the Vampire Slayer, the title character gains, rather suddenly, a 14 year old sister. That sister presumes she has lived all of her 14 years with Buffy and her mother, and Buffy and her mother and her friends presume that she has as well. The reason why everyone acts as if Dawn not only belongs in Sunnydale, in the Summers' residence, but also like they all have established relationships with her is because they remember her being there. Monks, in an effort to thwart an angry hell goddess from her goal of returning to her hellish dimension and killing all other worlds in the process, not only made Dawn into a 14 year old girl but also created memories and familial ties to go along with it. Dawn's creation and her forced inclusion in the lives of Buffy, her mother, and her friends is a violation of their autonomy and the sanctity of their memories. And Buffy feels that violation when she is confronted with the truth:
MONK: For centuries, it had no form at all. My brethren, its only keepers. Then the abomination found us. We had to hide the Key, gave it form, molded it flesh. Made it human, and sent it to you.
MONK: She's the Key.
BUFFY: You put that in my house?
MONK: We knew the Slayer would protect.
BUFFY: My memories... my mom's?
MONK: We built them.
BUFFY: Then unbuild them! This is my life you're -
MONK: You cannot abandon.
BUFFY: I didn't ask for this! I don't even know... What is she?
MONK: Human. Now human. And helpless. Please. She's an innocent in this. She needs you.
BUFFY: She's not my sister.
MONK: She doesn't know that.
What becomes clear is that Dawn herself is also a victim, perhaps even moreso, because she is the thing constructed.
In Dawn, there is a wrong being perpetrated against the other characters. Because of Dawn, there are no easy or right answers for how to handle that wrong. The characters have to live with that violation and within the 'verse and memories that violation has constructed. Anything less would be to willingly abandon an innocent 14 year old who had done nothing to instigate her creation. When Dawn discovers this, she begins a season-long downward spiral, and mixes that liberally with an existential crisis. And although there had been questions of identity before in Whedon's work, how we become who we are, what forms us, and what informs us, Dawn is really the first radical examination of how identity is constructed and what memory means. Dawn is the first character built on illusion, whose backstory - the very thing that informs her make up - is false. What the fifth season of Buffy the Vampire Slayer validates is Dawn's place in the world; the end of the season culminates with the idea that even though Dawn is unusually constructed, she is still human, she is still a person of worth, and she is still worth fighting for and dying for. What came before does not erase what is present in the moment; and when Buffy chooses to sacrifice her own life for the sister she hadn't had 9 months previous, what is emphasized is Dawn's own right to life.
What will be interesting about Dollhouse is that Echo and Echo's predicament is in essence an inversion of Dawn's situation. Dawn was constructed, her memories were constructed, and so who she is and what she does is built upon what many would consider a fabrication. Echo has the opposite problem. Echo will have real experiences she will not remember; Echo will have real thoughts she won't be able to recall; and Echo will have real learning experiences that at the end of the day will be stripped from her. And even though the pilot did not have that moment of forced revulsion Buffy's moment with discovering the truth about Dawn articulated for the audience, I think the premise of Echo's life is meant to cull up a feeling of disgust. From the opening moments where we see Caroline's somewhat coerced volunteering, to watching her memory wiped from her and the remnant token of the night's activities slip through her fingers, to watching Echo's Miss Penn dealing with the memory of an assault she never experienced, the creep-factor is there - and we are meant to recognize Echo's wiped existence as being a fundamental violation of her personhood, of her own self, as well as noting the strangely false authenticity that her different personas embody. What is perhaps all the odder is that it is not just Caroline we see erased, but every single persona Echo is implanted with as well. Eleanor Penn may have been an amalgam of different people, but for the time she existed within Echo, she was a person - she had experiences; she had faults; she had a backstory. Miss Penn died once Echo was erased, just like the motorcycle girl we never truly met died once the engagement is over. Every episode of Dollhouse will be a funeral procession of sorts - which is oddly perfect for Whedon, a man who never seems fully satisfied unless several of his characters are dead.
The very question of identity and what is an authentic and meaningful one is already in full swing in Dollhouse due to those factors. The question regarding Miss Penn's existence, if she was truly "a person, actual and whole" or if the inauthenticity of her memories made her okay to wipe in a way Caroline was not, is already out there, written into the very DNA of the show. Especially considering who came before her in the Whedon canon of characters. Because if Eleanor Penn's wiping creates no ethical quandaries or moral ambiguities, then what we learned from Dawn's existence is placed back in peril. If Eleanor is prime for being scrubbed out because the basis of her existence was not in the strictest sense true - if that contributes to her not equalling a full and adequate human being, then some of Dawn's own personhood becomes chipped away as well. But I'm inclined to believe that Whedon recognizes the inherent unfairness of the Dollhouse system for not only Caroline and Echo and Sierra, but also Eleanor Penn and the myriad of other people who are created and then erased from existence. Although it is more subtly hinted than the works before, there is the sense that something is rotten in the state of Denmark. And although I fully expect issues of agency and feminism and the nature of the greater good versus the rights of the individual will play a full and robust role here in Dollhouse (if the show progresses that far), I also believe that this question of what makes someone a person is the prevalent theme for the series. It just also nicely ties into the other issues present.