Canon mentions Astoria’s blood curse (from the Cursed Child timeline). Fics using this introduce poignant stakes: Harry falling for Daphne but needing to help save Astoria, or Daphne pushing Harry away to protect her sister. Weaknesses / Criticisms Astoria as a Plot Device In weaker fics, Astoria exists only to push Harry and Daphne together, lacking her own arc. She becomes the "magical cupid" rather than a person.
Even within Sister Act, Daphne is often still the stoic pureblood. Some fics forget that the "Act" implies she should show vulnerability — especially toward her sister. HDSister Act
The HDSister Act trope excels at giving the Greengrass sisters depth without derailing Harry’s characterization. When done well, it’s a heartfelt blend of romance, family loyalty, and Slytherin-Gryffindor dynamics. When done poorly, it’s a shallow matchmaking vehicle. If you enjoy pureblood family politics, protective siblings, and a slower-burn Harry/Daphne, this niche is worth exploring. Canon mentions Astoria’s blood curse (from the Cursed