Can I get away with stealing money from my mother?
Are you joking right now? Why would you rob your mother of money?
Because she didn't give money to me
That was not a nice thing for you to do. It is especially wrong to steal from your family. You should apologize and give the money back to her.
Cops wouldn't do anything about it, and it's not like she's hurting for the money. She even has a lot of money!
You don't know if the cops would do anything about it, if you are caught then they can and will pursue you. You need to reconsider trying to steal money from your family at all, because most people would consider that extremely wrong.