Mary and Percy Shelly traveled about Europe for a time. They struggled financially and faced the loss of their first child in 1815. Mary delivered a baby girl who only lived for a few days. The following summer, the Shelleys were in Switzerland with Jane Clairmont, Lord Byron and John Polidori. The group entertained themselves one rainy day by reading a book of ghost stories. Lord Byron suggested that they all should try their hand at writing their own horror story. It was at this time that Mary Shelley began work on what would become her most famous novel, Frankenstein, or the Modern Prometheus.