Need book recommendation for a cousin who is going through serious depression

Hello people.

So one of my cousin who is in 11th grade is not doing well mentally due to lot of issues at home and health. He has become extremely pessimist in life, which is understandable given the situation he is in. He has no friends as well. I have tried talking to him but it’s extremely difficult to do so. I want him to put in efforts for himself ( even tho I understand how difficult that can be)

I was thinking of gifting him a book which helps him get out of it. Can be a fiction which brings out lil hope from life or for him to feel relatable. Generally self help books requires a lot of dedication to read them so all in all if it’s something that keeps him hooked but also helps him.

Please recommend the books I can gift him, it would be of much help.

Thanks:)