I have 5 children. One gives the whole family 10 times more grief and emotional weariness then the other 4 combined. Convinced he is that we were horrible parents to raise them in an atmosphere of love and plenty as well as a place many called paradise.
Some people will never find happiness no matter the circumstance.
Their mother and I have had a 26 year love affair but he spends endless time trying to convince his siblings that our marriage is a sham.
Misery loves company and all I can say to families dealing with the same garbage is cut it out like a weed. He’s our oldest but we recognize the damage he will do to everyone else if allowed to remain inside the family circle.
Like Charlie he will screw anything. Inlaws, cousins and even the wifes of his brothers. This type of person is a cancer that must be removed.
It sounds like to me that he might be angry at the two of you for some reason.
Not saying that it’s for good reasons, because many people can be quite irrational.