my mom took out a reverse mortgage about 4 years ago and now is sick with cancer in a nurseing home but my sister and kids still live there

My mom left for the nurseing home in September 2014 who has a reverse mortgage but my sister still lives in my moms hiouse. My sister has 3 kids from ages 16years to 20 years old and fours cats. she does not pay any money for the house bills. I am the son Jerry who became the guardian of my moms estate. How do I evict my sister who still lives there and could the reverse mortgage company sue me for allowing my sister to live there so long