Sorry for the slow reply, the Yak Internet service has been especially slow this week for some reason. I blame the Yaks.
As for knocking some sense into the other parental unit in your family, that is a tough one. I'm not sure how you could do that, you know, without the help of a large stick.
Unfortunately, the large stick approach can not change the heart of your husband. I think about the only thing you can do, is make sure your husband knows your desire to adopt again (but not be pushy about it - men hate being "pushed/nagged"), and pray for his heart to change. Men find children scary. We find our wifes understandable. On a good day, we might feel that we have at least a slight grasp as to what is going on in our family. We doubt our parenting at times. And men hate - HATE to feel powerless, lost, confused or wrong. Or at least, most of the Yetis I have met have been like this.
So adoption is about the scarriest thing we can encounter. Can we provide for our expanding family financially, emotionally, etc... Will we contine to be a good father? Are we barely holding on now?!
So why spend a whole paragraph expanding on our insecurities? Only to say, if those are the reasons your husband may be doubting adoption - then you might need to give him very subtle loving encouragement that he CAN in fact adopt again, and that he CAN in fact be a great father to 1 more child, and that the family CAN in fact survive and thrive! Essentially, remove and address his fears/concerns without attacking or nagging.
Now, if he is stalling for a reason NOT listed above, then he is fair game to attack with a large stick.
If you DO use the large stick approach (which is my personal favorite solution to "conflict resolution") to help resolve the conflict, there may be some unwanted consequences. Apparently, the Child and Family services frown upon spanking, and beating people with large sticks is right out. Fortunately, we are dealing with a husband and Child and Family services may not really care if a husband gets it... so I guess the big stick option is still on the table.