Legal evictions,how to speed up Recovery of Premises

My mother is 82 years old and owns her home. Years ago ~ 17 she let my sister move back in with her. My sister has never helped my mother financially and she has threatened my mother on several occasions. My brother was also living with her until his death this past thanksgiving. My mother finally decided she was done with all my sisters abuse and decided to evict her. We gave her the three day eviction notice about 2 weeks ago and my mother has been staying with her sister. Today my mother wanted to get into her home for something and my sister refused to open the doors. The local police were called and my sister said she was not moving until she had to legally.

It looks like my sister has been throwing away my mothers stuff and has taken some of her mail. My mom plans on putting a vacation period on her mail. The main question is can we do anything to get my sister from stealing and destroying my mothers and dead brothers stuff. We started probate on my brothers few possessions. We are planning to mail in the eviction papers tomorrow to get that started. Could we speed up the process or get my sister out of my mothers home any sooner if we got a lawyer? Also, my sister took my brothers car keys and says she has no idea where they are now. The car is about the only thing my brother owned, but without the key we would need to get another made.

I have never dealt with anything like this and am asking for some advice on any of the above mentioned items.

Thanks
Jeff