[Dave breathes out and then sucks on his teeth for a second.]

Ummmmmmmmmm. Right, okay. This is where shit starts to get kind of weird, so...fair warning.

Bro was technically my gene daddy. And Rose's. And then her mom turned out also to have donated her DNA to our shared pool. And then John's dad isn't actually his dad at all, and Jade's grandpa was both of their dad, and John's nanna was. Well. You can probably figure it out.

...

This is where time travel starts figuring in.