My mom moved my sister and her husband and two kids in after her husband passed, they have stole from her numerous amount of times, my mom wants them out, but my sister says she's not leaving, that my mom will have to evict her out. They have lived there two years.. we live in Franklin Indiana, does my mom have to go through the process of evicting.

Yes of course she does.

Yes, she allowed them to live there so they have resident status. As residents they have to be legally removed.

So she gives them a written notice to vacate in 30 days or she will go to court for an eviction order.

When they see she is serious, they might decide to not have an eviction order on their record.