How do you know?

It is hard for us to believe, but Sudsy Pumpkin Pie will be 2 tomorrow. He is such a funny and happy little kid, even his terrible 2's are adorable. Hubby says it's time to start on #4. That sounds crazy to me. Absolutely crazy. And yet I won't completely rule out the possibility. How do you know when enough is enough? Or do some people (uhem, the Duggars) not ever know? We're out of bedrooms- is that a good enough reason to stop? I'm certainly not getting any younger and the risks go up exponentially every year. I think we have a wonderful family and I don't feel like anything is missing. Yet, when I think about the future, I know that we'd never regret having another child yet we might regret not having another one.

Someone talk me down, please!!!!