So, at last, they did.

When Caroline and her brother had gone for their wraps, Mrs.Dunn laid a hand on her son's arm.
"Now mind," she whispered, "see if you can find out anything during the ride.

Something more explicit about the size of their estate and who the guardian is to be.

There are all sorts of stories, you know, and we _must_ learn the truth very soon.

Don't appear curious, but merely friendly.