How would you react to discover that a family member keeps a deceased pet in a box in their home?

I just discovered this the other day during a conversation with a family member. The dead pet is kept in a pet coffin. I suppose since it is being kept above ground it is technically a crypt.

You may have questions but here are some pre-prepared answers:
No, I’ve never seen it.
No, I have no desire to see it.
No, I had no idea that there were businesses that specialized in pet crypts.
I have no idea if it smells. I assume the remains were embalmed and the box was hermetically sealed.
Yes the person is bi-polar.

I’m actually quite concerned about this. It raises a lot of red flags for me. It’s concerning to me because it seems like a symptom of something. Yes it’s possibly related to the bi-polar disorder but this behavior is totally new.