I just lost mom in July to SCLC. She was dxed in april and we took her right home to home hospice. They are truly angels!!
Mom was alert and semi coherent most of the time. She was weak and needed help walking, but she insisted on walking, even if only a few steps. Every day she was in the wheel chair for most of the day....in the kitchen giving orders
We even got some portable oxygen and took her for some car rides during this time. She never complained of any pain at all.
About two days before she passed, she stopped eating. We knew then, the end was coming. She was a little more lethargic and resting more. On her last day, we could tell her lungs were filling rapidly. But again, she didn't complain of any pain.
I was holding her hand as she took her last breath. It is a moment I will never forget. I was able to be with my mom in her death, as she was with me when my life began.
Hospice will not let your sister suffer any pain. I do believe once you make the call to hospice, the ONC will no longer be involved as you have basically said "no more treatment". It might take hospice a few days to get the meds right to make your sis comfortable, but once they get the right doses, it's clear sailing.
Appreciate and cherish the time you have. God Bless