Live and let live. MY sons are going to make mistakes, sin and outright walk in rebellion, but they are yet sons of God. I AM perfecting them, as I AM perfecting the unpolished parts of you.
Have some grace, some mercy and learn to forgive them. What you are discerning is privileged information and you are privy to it, that you may intercede in the spirit realms.
This precious intel is not to gossip, slander or to be used to look down on others. It is a call for intercessory prayer warriors to take action. Where sin is plentiful, MY grace is sufficient.
If your brother has a character issue, this is not a call to exploit, but a demand placed on what you carry. These imperfections are the work, the assignment and the cross chosen for you to bear.
As a prisoner for the Lord, then, I urge you to live a life worthy of the calling you have received. Be completely humble and gentle; be patient, bearing with one another in love. Make every effort to keep the unity of the Spirit through the bond of peace. There is one body and one Spirit, just as you were called to one hope when you were called; one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all.