No, I would not disown them.

My children would know full well what I thought of such a decision, but disowning a child is an admission of defeat. In every case I have seen something like this happen (i.e.: disowning a child), and have spoken with both the parents and the child, I have in the end formed the view that it was a failure of the parents, even though the child is responsible for his or her sinful actions.

A good father and mother will wear the spittle and derision in the streets that comes from having a black sheep. Sometimes the defense of the guilty is as necessary but even harder than that of the innocent.