Animation

The synopsis reminds me of the animated film "My Neighbor Totoro". Although Totoro is very lighthearted, it still has to do with children whose mother is in the hospital trying to overcome an illness and a forest spirit that comforts them. I don't know much about "A Monster Calls" but the synopsis of the movie shows similarities.

I agree! It reminds me of The Iron Giant in some ways!

I think animation is still relegated as sort of a niche art and most directors wouldn't immediately think of it as a medium for the story they want to tell. It's almost like, "we have John Lasseter and Hayao Miyazaki to make animated movies, so everyone else can just stick to live action." haha

I just saw a cut of the film, and they do incorporate 2D animation into parts of the movie in the parts where the monster is telling his stories. I thought the film did a really nice job of implementing both animation and CGI, as well as having lots of lovely shots of hand-drawn images. It's a really gorgeous movie, both visually and in its story.