Question: What sort of message does this send to your children, that you allow your father to treat you as a 2nd class citizen, and openly disrespect you in such a fashion?
Families are a package deal. Not willing to accept your life decisions? Want to shun you, yet still expect you to serve up your children to be brainwashed at their convenience to also eventually disrespect you? I'd tell that azzhat to promptly go get fugged!! And I'm not just saying that, I had similar happen to me and that's EXACTLY what I did. No one shits on me, then gets to still see my children.
I would NEVER let a brainwashed cult member around my young children unattended. EVER. They will do everything in their power to indoctrinate them with their bullshit, and drive to divide and conquer.