An important theme of the story is the acceptance of change. The main character Mary Lennox helps Craven understand that, and shows him he can still love.

Fuck normal.” [Varick] took [Kieran’s] crumpled wrapper and slowly straightened it out on the table. He began to fold it in half, then half again, and finally one last time in half, making a neat square. “Normal is a societal construct that is created by people. There is no consistency across civilizations or cultures. What is normal to one person is not normal to another. It once was normal to own slaves and be prejudiced against people of color like yourself. It was once normal to make women wear dresses and cover themselves. And long ago it was normal to cut off someone’s hand for stealing instead of putting them in jail. Eventually, all societal constructs fall to new ideas. Normal is one of them.” Kieran stared at him with his mouth slightly open. “Now, just fold up your silly wrapper like you want to.

Change is never an easy thing to accept even when the norm regardless of its ugliness is the norm.

Inorder to accept any sort of change, you must realize that you do not have control over everything in your life.

If you really love someone,' Claudia continued, 'you have to be prepared to accept them as they are. Maybe you hope that one day they get a wake-up call and make the changes for their own reasons.

Strong character is brought out by change, weak ones by permanence.