Okay so I know that alot of people have previously asked these suggestions and I've tried doing my research too but just for confirmation I want you guys to choose one or two books from this list or suggest something else if it's better. I don't want the books to have cancer as the main focus but just something to help her cheer up and feel motivated to fight it through till the end.
For reference by best friend is 21F, really loves Harry Potter series, is a big fan of poetry maths and science. Also she's read and loved books like kite runner,forty rules of love etc etc
The books I've come across as suggestions are
1) When breath becomes air
2) The unwinding of miracle
3) the midnight library
4) A Monster's call
5) Garden Spells
by soft_suffering