Pearl and Ruby - two precious gems - are friends for life.
For eighty years, from the very first day they are put together in school, Pearl and Ruby are firm friends, through all the weddings, children, grandchildren and even great-grandchildren.
The world around them may change but their friendship remains strong.
We first meet them, aged nearly ninety, dealing with all that old age brings. Through flashbacks, we find out about their long, mainly happy, lives, how they met their husbands and the joy of children.
Their children grow up together and are firm friends. They take great delight in each other's grandchildren and great-grandchildren, and have many happy memories to share, as well as the sadness for those who have already left this world.
But how do you deal with the knowledge that your own life is probably coming to an end, even if it is after ninety years?