Thanks to all the reply, this is the best thing in my life.....means everything to me.
The risk of miscarriage does go down with every passing week, then you'll enter the second half in which the odds of survival rise every week (typically after 24 weeks but they are saving some babies born pre-24 weeks now!). I am always so impressed when I see posts from you since you are obviously a very dedicated husband and father-to-be. Keep it up!
You can google statistics on these things but if it helps, after hearing the heartbeat at 11 weeks, I was told the risk of miscarriage was below 2%.
Since you heard the heartbeat at 9 weeks, the chances of a miscarriage now are very low. You aren't out of the woods completely - not until you reach 13 weeks. But you can relax a bit knowing there is less than 5% chance at this point. Congrats!
Miscarriage can occur at anytime but most commonly happens in the first trimester. She only has less than 3 weeks till the chances of it happening drop drastically :)