Why does Cole Hale go to the pawn shop in Part IV, and what happens afterwards?

Cole Hale goes to the pawn shop in Part IV to recover some of his mother's beloved porcelain figurines that she had been forced to sell before her death. After the shop's owner gives Cole the address of the person who bought them - his father's former mistress - he goes to the mistress's house, and she kindly gives them all back to him.