I'm looking for stories that follow the basic premise of a father's wife/ex-wife is a bitch. The daughter thinks she would be a much better partner for the father and sets out to seduce him.
Bonus points for all three hikes open for him and pregnancy but the main premise is what matters.
You can try Mother's Little Helper / Her Mother's Daughter by rache.
It's two stories. In the first the mother finds her life collapsing due to a drug habit. In the squeal, her daughter moves in and takes her place. There's a really good bit where the daughter has the father take her on a date. They find the mother working as a prostitute, hire her and have fucked up sex.
