Adult Thriller; read in 2013. Girl who boxes seems to be followed by a killer and is entangled in strange circumstances. Spoilers ahead.

[Rezkian]

Intro begins to two young sisters in survival mode as their mother has clearly trained them to be ready to escape something dangerous and utterly horrible--but it turns out she's mentally ill. One of the girls (protagonist) grows up boxing (not professional?) mostly as self defence and stress relief.

A murder seems to be related to her? There's a lady who shows up halfway through who -SPOILER ALERT- turns out to be her sister and the murderer. One of the victims COD was insulin overdose despite likely not being diabetic.

Read in 2013!!! It was a crinkly paperback in Illinois

Sorry for the lack of info!!!

[Kris]

Rezkian, how old are the main characters? Is this book for adults or teens?

What's the location (country, region, well-known city, small town)?

[Rezkian]

This is for adults and it was some american city like NY or chicago type mood. Characters were in their late twenties early thirties by most of the book (beyond the intro where they were little girls)

Kris wrote: "Rezkian, how old are the main characters? Is this book for adults or teens?

What's the location (country, region, well-known city, small town)?"

This is for adults and it was some american city like NY or chicago type mood. Characters were in their late twenties early thirties by most of the book (beyond the intro where they were little girls)