[Okay, this is far from Zuko's area of expertise, but Rin doesn't need her being super awkward about it. Anyway, it's not like she's never thought about having kids, she just didn't know much about how that works. She takes a breath.]

Calm down.

I know you're not ready to be a mom, but if that's what happens, you'll get through it. And you won't be alone.