Nothing is more dreadful in a person than disloyalty.
Since your elder brother and your younger brother have of their own accord become enemies of the Lotus Sutra and abandoned you, they are the disloyal ones, and you yourself are not to blame. But if you neglect to look after their wives, you will certainly be acting disloyally. Should your fief be enlarged, provide for them out of your own stores, sparing no effort to ensure their welfare. Only if you do this will your deceased parents protect you without fail, and will Nichiren's prayers also be answered. No matter what faults your brothers' wives may exhibit, pay no attention.