Shrinking Statue

Q: I have a small white stone statue of a wolf and a girl sitting face to face. It has been in my mother’s family forever. Several years ago my father gave it to me because he thought it was shrinking. I thought he was nuts at first, but had to agree when I noticed that the wolf’s legs and the girl’s arms had gotten thinner. I placed the statue under a glass dome and wonder if there’s more I can do to preserve it.