I was with a friend when her child passed away. I cannot be critical of how anyone handles a child who is gravelly ill or who has passed on.
Anger is simply frustration for not being able to control a situation. The hospital staff is very used to this behavior.
Cliging to God I understand too. It's far too painful to believe you may not ever see your child again. Only religion guarantee a reunion in the afterlife. These parents face enough reality everyday. Let them have their fantasy.
There's no right way or wrong way to handle grief of that magnitude.

I'm going through something similar with my sister who has cancer. She has a distrust of the doctor trying to help her saying they are only it for the money, but is all about "god will see me through". So far I've just sat back and kept my mouth shut. The iron of the whole mess is I would be just the opposite, listening to every doctor trying to educate myself while I know my sister and my mom would be the spearhead of "you need to accept jesus into your heart"
I have no choice in the matter other than being silent if I want to be a part of my sister's life. I guess you have to ask yourself how important is your friendship. If you want to keep your friendship, you'll have to keep your tongue. Every relationship is about compromise, I think that is why it is hard for atheist to be friends with theists because that's something that neither side is willing to compromise on.

As a healthcare provider, I have to admit this grates my nerves. If someone gets better they'll say Jeebus was guiding us. If they don't get better, they sue us. I might gently remind her that if the hospital had nothing to do with it, why not just take the kids to church and forget about medical intervention?

Shame Jesus wanted their kid to get lukemia, but wonderful the doctors and nurses are ready, willing and (hopefully) able to fight God's will.

Be there for them, they are your friends and they need all support they can get. At a point of despair, right or wrong beliefs don't matter, what matters is the support you might get from your close ones. Put your heart in comforting them.
What matter to you their wellbeing or their beliefs?

Much of that anger and frustration comes from your perspective. It is not surprising behaviour that a believer would ascribe praise and put their trust to the being they believe to be in control of the situation and it's outcome. View it this way and you can begin to let some of that frustration go. I would also start modeling the behaviour you wish to see from them. In other words, ask pointed questions about who the stars are at the hospital who have been excellent through their child's treatment. Give the hospital team praise in those conversations you are part of. It might become that, when talking with you, they begin to frame their thoughts around how to tell you events concerning the excellent care the child is getting.

They are vulnerable and they are clinging to God for comfort. Without vulnerable people like them religion will disappear.

Friendships, like relationships are two ways. You both need to be getting something out of it for it to be a health friendship. You need to ask your self what are you getting out of this other then frustrated.

When 'believers' are so addicted to their Jesus concept that they can't ask themselves where this damn Jesus was when their child was getting sick, all you'll do if you countradict their 'faith' is drive a wedge between you two. I would consider how important this relationship is to you as a starting point, as one comment against their addiction might blow it all to smithereens.

Your call, your call. I tend to ignore, I don't have beef with worship so I ignore. I will remember I am not the one sick so.... is not about me.

meh. they needed their beliefs for hope and comfort. thats what beliefs are for. they are the ones who needed the comfort, not you. I'd say leave them to their fairy tales at that point.

Just keep mentioning what a great job the doctors and nurses are doing. Never bring up the question "Why would Jesus allow him to get lukemia?"

Bear with her. If it comforts her, and she's not with-holding care, let it be.

When I run across something like this on FB I always post something like... I am so glad science worked to provide the doctors a way to save her. Or I say I hope the doctors know just what to do to help.

Sadly there are people who fail to give credit where credit is due. Iv made it a point to acknowledge any and all care takers who are dismissed. When you friend begins with her praise, quickly let her know that there are several mortals here on earth who have done the hard physical ground work and fight the fight with more than one.

If your friend is remotely cognizant of life, she will eventually recognize those medical staff who care for the child. I hate to say that eventually, when the child succumbs to such a terrible disease, she will either still believe in the fairytale or turn her back on religion all together. Whatever her choice, whatever her decision, the physicians and other medical staff will never get the recognition they deserve and she will blame them as well as GOD for her pain of loss.

Let her praise who she shall and eventually, she’ll come to know the true meaning of falsehood. Sadly, we have no control over the naivety of others and can only create a clear mind for ourselves.

Best of luck to you, here’s to improved health of the child and be thankful there are those who have the heart and compassion for such work as it is surely defeating for the most part.

Send her your thoughts and prayers.

Whatever u feelmost comfortable doing.

If it was me, I'd tell them about cannabis oil, and distance myself if necessary.

Landmark Study Shows Half of Cancer Patients are Killed by Chemo — NOT Cancer [thefreethoughtproject.com]

BBC News - Growing evidence that cannabis oil can cure serious diseases like cancer [bbc.com]

Buy me a jet.

You will never say or do anything to convince her otherwise, she'll need to discover on her own what the truth is, as frustrating as it is to stand by and witness this. It is really a shame how all the hard working people that care for and help these people get no credit or really even any thanks, BUT, it is the world we live in. As long as those good doctors, nurses and helpers can go home at night and look into the mirror and KNOW the score, I guess that is all that REALLY matters !!!

Lol OP is virtue signalling