Why does Nora question Anne-Marie about her daughter ?

Nora is feeling Anne out to see how her own daughter might react to her leaving the family. She is also trying to ascertain if Anne would remain to care for her children.

Nora. But I suppose your daughter has quite forgotten you.

Nurse. No, indeed she hasn't. She wrote to me when she was confirmed, and when she was married.

Nora [putting her arms round her neck]. Dear old Anne, you were a good mother to me when I was little.

Nurse. Little Nora, poor dear, had no other mother but me.

Nora. And if my little ones had no other mother, I am sure you would--What nonsense I am talking! [Opens the box.] Go in to them. Now I must--. You will see tomorrow how charming I shall look.