They came together to help him.
Yes, I was affected quite differently as an adult compared to when I was a teen. Especially now that I have children of my own. It's almost impossible to imagine losing a child.
What stands out most to me is that it is a period piece. It's about a time and way of life that isn't much with us any more. Catcher in the Rye is the same way for me. We've had discussions here about that book, and some maintain that it is absolutely a classic, one that everyone should read, while I feel that although it's definitely worth reading, Holden Caulfield is a representative of a class system that is essentially gone: he attends and gets kicked out of many private boarding schools, and that boarding school system is not as influential as it once was. Most kids today can't identify with him. It's also in relatively recent years that Catcher has become one of the books high school students read. Back when I was in high school in the 1960's it was all but banned, mainly because of the language.
In Death Be Not Proud the private boys' boarding school Johnny attends is one of those that in those years could simply send the boys they wanted to Harvard, to Princeton, to Yale. Yes, they needed to take their college boards, but the recommendation of the headmaster would almost invariably clinch it. Notice that Johnny isn't applying to several schools, but is simply planning to go to Harvard.
The book was totally worth the reread, and I'm glad your mention of it here got me to do so.
So for me this book is mostly a window into a long-ago world. One in which almost nothing could be done for cancer. Notice that they did surgery, then radiation treatment, and finally one of the earliest versions of chemotherapy. Now there would be so many more things that could be done. A child with the exact same brain cancer would at the very least live much longer, and perhaps could be cured.
Another thing that for me was quite weird was that the many insightful or odd things that Johnny said kept on sounding to me very much like the son of a close friend of mine. My guess is that the two very intelligent young men, separated by two generations, simply have a lot in common. Nonetheless, I kept on hearing Brian's voice when Johnny was quoted. Brian, for what it's worth, is now 32 years old and has never, so far as I know, had any serious illness of any kind.