The ex-wife who raised her daughter has cancer. As an ex-husband, what should she do?

Although divorced, the child is still biological, and the mother is unable to raise it because of illness. As a father, you should take care of your children's lives. If you can help your ex-wife's illness, if you have a new family and communicate well with your current one, you should generally be considerate. No way, others can't say anything about you. After all, you are divorced. It's not good either, because the ex-wife caused new family discord. There's not much else you can do. Mainly children, discuss with your ex-wife what to do with the children. Don't hurt the child because of this.