How to get data from third table in eloquent relationships eloquent many to many relationship

I am using Eloquent ORM and I have Book model which connect to BookCategory model and BookCategory connect to Category. The l'm problem facing is how to include data from third table in eloquent relationships?

Book
    id
    name
    
Category 
    id
    name
    type
    
BookCategory 
    id
    book_id
    category_id

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