7year old niece steals what to do?

Tell her parents to man up and spank her every time she steals something. She'll learn to not steal pretty quick. She has to understand what consequences are. People should not be afraid to spank their children. It's not cruel, it teaches them important lessons.

your telling a 7 year old "The consequences" you mental, why the hell would she care about consequences??? she 7? put her on the damm naughty step each time she steals for 3 mins plus her age so 10 minutes at a time and if she moves just put her back, havent you seen super nanny?

Something bad is or has happened to this child. Are you in loco parentis to this child and if not why are people complaining to you? If I had to guess I would say she is or has been sexually abused, she feels guilty but cannot remember what happened and doesn't understand it so she does something to feel guilty about. She needs a full workup by a child psychologist.

i used to steal when i was about 5. Its not that I was trying to hurt people or anything, I just did it?

What 'taught me my lesson' was when my aunty told my mum i had stolen her lip balm & my mum made me apologise to my aunty & give her back the lip balm. I was so scared & never did it again!

try that.

Take her down to the precinct, the cops will likely play along and give her a little scare.

steal from her and take her things and if she doesn't like it then tell her that everytime she'll steal something you'll take something valuable from her