A deceased Aunt

Okay, I know the headline sounds ominous, but it's not as scary as it sounds. For the particulars, I'll be brief.
About 3 years ago, my mom came down with Colon Cancer. A year after that, and 3 surgeries later (which left her unable to travel), my Aunt (whom lived a province away)found out she had Lung Cancer, and went pretty fast. My mom was unable to visit her as she was passing, nor able to go to her funeral.
About a year and 4 months ago, my mom's Cancer had returned as an inoperable mass in her abdomen. As of now, she is alive, but in chronic pain due to this mass (which has grown considerably) pressing on her various organs and spine.
For the past 3 months, my mom had grown a bit restless (not wanting to sleep, needing someone to be with her around the clock)...mind you, me and my sister live with her (I've basically lived with her my entire life), but you get the jist (I hope! lol).
So, tonight, I had a dream, that my deceased Aunt was visiting my mom. They were having a good visit...then my mom told my Aunt that it was time to go to sleep, and my Aunt became enraged. She had picked up a statuette of Mary, and flung it against the wall (though it didn't break). Then I woke up.
I believe that my Aunt is haunting my mom, making her feel restless. It may be due to the Cancer, but things feel different, because she (my mom) had come to realize her mortality...not only with this illness, but with other factors that have happened in her lifetime. My mom had told me many times before that she was ready to go, not only during the different stages of this Cancer, but beforehand as well (long before this Cancer came into the picture).

What I am asking in this thread, is how do you (if possible) tell or make a spirit go to rest?

p.s. I also welcome any dream interpretations. Thanks! wade:)