Two, One, Two

I lived in a two dog family for several years. Then, I moved back to a one dog family. Now, I am thinking of becoming, once again, a two dog family.
You see, I made a promise. Now I have to live up to it. That means we are getting another dog. We have been looking on Petfinder.com to try and land a cute, cuddly, even-tempered dog to love and nurture. I am quite a bit scared, though. This dog must get along with Maddie, our other dog. First, I understand she will be very, very upset. She probably will not like the other dog. I get it. I wouldn't want to share everyone's affection, either. It happens, though. So, she must deal with it. The whole situation makes me nervous, however. I want the two dogs to get along and not nip at one another, or rough one another. I probably won't get what I want there. I want them to be buddies. But how can I know that will happen until I have already adopted the second dog and brought him home? Ugh.
So, tomorrrow I will make the trek to a humane society that has a dog we've been eyeing. And we will meet him. And we will cuddle him. And we will do the "paw test". (This is when we try and grab his paw to see if he throws a fit. If the dog lets us hold and rub his paw, then he's good. -- Yes, this test is unofficial, but I did see and hear it on Puppies 101 the other day; something very similar was explained, so I'm right, right? Sure.) We will more than likely fall in love with this creature, and I won't be able to resist putting a down payment on him. (He's not available to go home with a family until May 14 due to neutering.) Wish me luck. Johnnie might be ours.