The missing sister

Growing up, you knew of a family that didn't want anything to do with you, a family that had left you behind. You didn't know if it was a good or bad thing, your mom said it was a good thing, their life was a constant move from place to place with very little life in between.

For you things are normal, you have a little sister named Francis, you call her Frankie. Life is normal, till your mom brings home a new boyfriend that she met at her housekeeping job at the hospital and suddenly, things are off.

Off to the point where 2 men show up and start butting into your life like they know you. Or want to know you.

This will be a Castiel/reader story