Great news about your gals success with house training !!
Now for Brody, you really do need to watch him like a hawk...the tiniest drink of water will mean a trip out to potty ! If he does not go, take him right to his cage and wait a few minuites and than back out to go potty again. This works every time. (a cage is really a great tool when it comes to potty training)
One good think is that your gal Sophia will be a great help showing him what to do. Take them out together and let him smell her puddle. From my experience with multiples they will normally go right where the other left off.