I decided to comment here, because so many people have expressed doubts about whether they "should or shouldn't" see a dying parent. I say, use caution, and here's why:
Recently, my estranged sociopathic mother got me sucked into an estate lawsuit (I won't even go into it) with other relatives. We ended up discovering that she had scammed her brother, me, my brother, and the other relatives. No surprise to me.
Due to the lawsuit, I had no choice but to interact with her, even though I'd successfully stayed away for about 10 years. She made a big act at her nursing home about how glad she was that I was back in her life etc. and I made a good faith (but nihilistic) effort to legitimately get along and help her. Throughout her nursing home time, she suffered from episodic "near death" occurrences. We would be called and told she was about to die any moment; but then she would recover. This happened repeatedly over the period of many years, and it entered into why I had to be involved as her agent as well as a party in the lawsuit.
Once we were able to discover what really happened in the lawsuit, we settled with the relatives. My mother then became blatant again with her chilly, destructive, murderous behaviors. And, throughout the lawsuit, even while she was pretending to be nice, she succeeded in ruining my credit, causing me to lose my home, destroying my health, and turning several people against me on false pretenses. That was her standard protocol in dealing with me since I was a child; that's what sociopaths do, and they never stop doing it.
I of course ended the relationship again as soon as I was no longer legally entangled in the estate lawsuit. By that point, most people were on to her, and her continuing efforts to ruin my reputation to anyone she could get to listen to her usually fell on deaf ears. Shortly following all of this, she started having those "near-death" episodes more severely, and recently passed away alone, having alienated everyone who knew her.
I shared this because I want to say that, if you have the kind of parent I did, you should NOT get back in touch with them. There are some mental/personality disorders which never go away. If your parent has such a condition or, for whatever reason, has always been abusive to you, then nothing is going to change. As I discovered, someone like this can do incredible harm to you and your life even from a sick bed. It isn't worth having your life ruined to try to be nice to someone who wants to hurt you just because they are dying.
Even if your parent isn't able to do actual physical or real harm to you, they may have a continuing desire to harm you emotionally or psychologically. You will be in a vulnerable state most likely if you are there with your parent dying and having a troubling past; I don't think it would be wise to be exposed to such a risk.
I'm sure that God will understand your decision if you stay away, regardless of what some bleed-heart relatives, friends and associates may think. Please decide fairly for yourself. Of course, if your estrangement is over something nonsensical in the grand scheme of things, then you probably should try to resolve that, since you'll both feel better. But in situations where you parent was truly abusive, I say, don't do it.