I think losing a parent at any age is emotionally challenging. Often we don't know what to say. I know when my mother-in-law was battling cancer I was amazed at how courageous she was. Not only did she focus on maintaining a positive attitude but she was constantly researching various ways to battle cancer. A good friend of ours noted that the gift cancer gives you is time to say goodbye. A couple of months before my mother-in-law passed, she had surgery that revealed how much the cancer had spread. My husband prepared himself for her eventual death & came to peace with what was coming. I encouraged him to reach out to his friends as I knew I could not be his only support. When he did reach out to his friends so many had stories of how they lost their parents & how they coped. My husband was lucky that he was able to spend one of the last weeks of his mom's life with her. They had amazing conversations & he was at peace when she left. As a therapist I understand how complex grief is & as a human I can only imagine how hard it is to lose your parent.
I've included some links to some articles & helpful tips about coping with the death of a parent.