The ex-wife came to pick up the children and said something.

You need to find out why the child is crying.

I understand whether the child can't bear to cry separately from his mother.

It's even worse if you don't let the mother of the child have more contact with the child. Divorce does great harm to children.

In order to avoid bringing more harm to children, let children spend more time with his mother to make up for the lack of maternal love.