So does this mean that when Christians tell their own children that they are going to hell is also abusive?
If you mean parents, or anyone else, telling children there is a heaven and a hell then of course it is not abusive. Telling anyone the truth is not abusive. If you mean parents, or anyone else, telling a child, or anyone else, they personally are going to hell then they are simply putting themselves in place of God. Only He would know and only He is the judge.