Sister Trope

Everything About Fiction You Never Wanted to Know.
Mini-Dress of Power[1] and Sexy Santa Dress[2] are both skimpy dresses for Fan Service, but otherwise different purposes.

What happens when The Glorious War of Sisterly Rivalry switches genders? Cain and Abel. What's the difference between The Scrappy and a Creator's Pet? Authors love their Pet. Is this introductory paragraph trying to explain by example a Xanatos Gambit or a Batman Gambit?

When defining a trope, it often helps to establish its similarities, differences and relationship to other tropes; a common convention on this site is to refer to some tropes as Sister Tropes.

When two or more tropes have some overlap in their descriptions, "parentage", or use, but not enough for one to be a Sub-Trope or Super-Trope of the other, these are called Sister Tropes. That is, both have a similar form or function, either by category (character, plot) or by effect (characterization) rendering them both similar but distinct enough to be considered equals. Not that there's anything wrong with subtropes!

These are the four Trope Sisters, each more lovely than the last:

Sometimes when two distinct tropes serve almost exactly the same function or have very subtle differences in description, it can reach the point that they are used almost interchangeably. Bad Flanderization! Bad! The Canonical List of Subtle Trope Distinctions is your friend.

Examples of Sister Trope include: