[ID: Quite soon before he died I realised that I had a special bequest from him. He gave us many gifts, and among them he gave me a real knowledge and deep love for mythology. I started with his classical pantheon and with the tales from the Old Testament, and these have been tools of my thinking and working ever since. In Jane Lazarre's book On Loving Men I read that in classical mythology, that bloody and treacherous web of connections and hatreds, there is no story in which the daughter kills the father. I was taken aback. I searched high and low. I sifted through the equally blood-strewn corpus of the Bible. I extended my research into other mythologies. I thought to myself, 'Oh ho, here is male dominance at work, this is the one tale They cannot afford to know.' Then I started looking at historical murders, the ones that make it to the sleazy annals of crime literature. Women, I discovered, after travelling in some pretty gruesome places, do not murder their fathers. Or do so very seldom, and under very bizarre circumstances. It is an extremely rare crime. Women murder men - their lovers, their employers, their children, their rapists, their ancient uncles, and the victims of stray meetings on the street. Clytemnestra drowned Menelaus in the bath; Jael made a bloody mess of Sisera; Myra Hindley mutilated children. Nothing can be universally claimed about women's gentleness, their lack of violence, their tender loving hearts; but they don't kill their fathers. If we don't kill our fathers then I could not have killed mine. Why did he, who taught me so many things, never teach me that my anger would not kill him? Or me? Or our love? / end ID]
Sara Maitland, Two for the Price of One
at the end of the day, vampire or not, your father is just Some Guy. the guy who made you is about just as vulnerable as you—and you can't be invulnerable, because otherwise how could he have hurt you? how could he have made you? a father needs to be unattainable somehow, which means you need to fail to reach him every step of the way.
[ID: I have another father. This one is alive and well and rampaging inside me. He never goes away, although sometimes he is silent; he is never ill, never weakened, never leaves me alone. He lurks about under other names - God, Husband, Companion, and all those relationships are made possible (which is nice) and impossibly difficult and conflicting because of the Father who is in and under and through them all. / end ID]
...and Louis to Daniel in episode 2, "Lestat, my murderer, mentor, lover, and maker. I worshipped him."
Father the God is interwoven with Father the Human (or vampire). the divinity of creation cannot be separated from the reality of flesh and bone. the creature can only eliminate the possibility of destroying his creator by rendering himself powerless.
and the gender dynamics of the daughter specifically being unable to kill the father ... claudia is forced into the position of daughter and ultimately rejects it, but louis embraces it. he has to! as a husband (/wife), he can kill lestat; as a daughter, he cannot.