In "The Devil's Arithmetic", who does Chaya say can be her second best friend because she already has one?

The girl who suggests to Chaya/Hannah that they can be best friends is named Rachel. They meet her at Shmuel's wedding. Rachel introduces her to other girls and, thinking that Hannah is Chaya, a young girl whose parents have died and who is new to the village, says that she will be her best friend. But Chaya/Hannah tells Rachel that she already has a best friend named Rosemary. She tells Rachel that she can be her second best friend.