that is a world wide problem.
I can tell you for sure there are mothers who lie to their children about the true character of their father just to gain the full love and loyalty of the children.
once there's friction btw both parents. some mother's use such to paint the father black before the kids. it happens and I have seen it happen. which contributes to the sweet mother.... we all sing, as if fathers are bitter
well mine isn't I loved him till his last day.