Given the story, I think they can. It's actually quite funny that this film, with a couple of flashbacks to the kids, will probably be closer to the book. The first film is already a pretty damn fine adaptation but this will be structured much like the entirety of the book lol. Not to forget that this is almost three hours long and the mini-series from 1990 is three hours long and handles the entire book whilst the first film has already covered a whole lot from the book.
It really is the best way to adapt the book to film and I can't wait to see this one. It has all the right ingredients to even become superior to the first film.