Pray for my sister's illness

I want a prayer request for my sister's illness. We found out in last May that she was diagnosed with Hodgkin's Lymphoma cancer. More recently we thought she was getting better, but her most last examination told us that the cancer returned again. We happened to have a couple other members in our family who was diagnosed with the same cancer at one point.

Hearing her have to suffer from pain at least once every day really bothers me and makes me more sad than I have ever felt before. None of us had any real personal experience with cancer itself before.

Please pray that she will be strong and feel better.

An update, my sister is doing better and has recovered twice.