Taking Back Something You Said?

I've been doing this more and more lately.. saying something, then regretting it.  Today i met an acquaintance from childhood and here's the dialogue:

Me: "Hi, it's so nice to see you"
Him: "Yeah, good to see you too"
Me: "So how's your daughter?  Does she have a kid yet?"
Him: "Oh you don't know.. she got a divorce"

Awkward silence...

Then i remember that i knew i heard the news before, but it just slipped my mind.  I need to think more before i talk.  But sometimes, when you want to say something and hold back, u miss the moment to say it.  Arrg.