TAS Sister in law mentally and physically abuses her sisters

[Bengali]

Hi as I posted before, my in-laws are just terrible, I can deal with it, but I'm afraid children can't.
My inlaws have 3 daughters, an 8 and 9 year old and I believe the eldest is 19.
The eldest is usually quite aggressive, she snaps at the little girls for almost anything they do (swears and screams at them) and has many times physically hurt them. I won't go into details but I will say the little girls have come to me and my partner (their brother) seeking comfort. That was during the time my partner and I were dating and he was living with them at his parents place, less than a year ago. My partner and I moved in together shortly after because I couldn't stand the abuse to the children and how they were being treated.
Both my partner and me brought to attention the way the children were being treated to the parents. They chose to ignore it and even blame me for the children hating their older sister.

My husband and I will be going to the police tomorrow due to his sister and parents harassing us and were wondering if we should mention we are worried about the welfare of the kids?
Also, what will they do if we do mention the children being abused, will they take matters to court or give parents a warning?

Hopefully I placed this in the right section.

Thank you

 

[AllForHer]

Police is a good start - your partner may be able to apply for a domestic violence order against the older sibling and name the two younger siblings as protected parties / but you should also contact DOCS for advice on this.