A house full of old souls

I found myself having this conversation today:
Kate: I might die before you.
Me: Why would you say that? That would make me sad.
Kate: But if you die before me, I would be sad. (she pauses) Let’s die at the same time.
Me: Then everyone else would be sad.
Kate: (She thinks for a minute.) When we die, do more people come?
Me: Yes.
Kate (smiling): And then it’s our turn again — again and again and again.

We have never had a conversation about reincarnation. She came up with this notion on her own. I am living with an old soul.