Hello,
The Moody surname project I was referring to has been conducted via FTDNA. As the other "replyer" gave the link to the site, this should be of help to you.
You mentioned your son did a test. Is he a born MOODY?
If so then you already have your Moody family HaploType.
You mentioned a brother who is willing to do the test, so again, you just have to be certain that he is a born MOODY otherwise his Ydna (the male side of the dna test in this case) will not be accurate.
I hope you will have your brother do the test as we now have about 90 participants and your chances are Very High that you will match Ydna with others in our group and finally know once and for all without anymore guessing, which branch of Moody's your line does belong to.
Best of luck to you and do stay in touch if your brother does agree to do the test and do let us know a brief lineage line for your branch of the Moody's.
Its always great to possibly meet new Moody family "cousins". Take care.