Mary and Adam are overjoyed to learn that they are going to become parents. The idea of grandparenthood is pretty thrilling for Charles and Caroline as well.
As the time moves along, Mary decides to contact Adam's estranged father whom Adam has not seen in a very long time. Needless to say, Adam is not pleased when his father turns up in Walnut Grove but things improve greatly when it's clear that the older man wishes to make amends to his son and get to know his daughter-in-law and grandchild. Adam is startled when his father wants them both to move to New York and live in luxury with him where Adam will study law.
Both Mary and Adam are delighted to accept ... or are they? When Mary suffers a heartbreaking miscarriage, Adam's father suddenly has a change of heart and tells Adam that perhaps the move to New York wouldn't be such a good idea after all, making Adam realise that his father only ever wanted to have a sighted grandchild and was not interested in himself and Mary at all. He lies to Mary and tells her that it was he who changed his mind and learns that Mary secretly wanted to stay where she was anyway.