"How I wish I would arrive tomorrow and surprise you. Who would be happier? You or me? Probably me," Carl Howe, an American soldier who fought in France during World War I, wrote from the battlefield.
The letter was returned to the family after an investigator found it for sale more than 100 years later on the eBay platform. "Not an hour of the day goes by without me thinking of you," he said, "the many good pieces of advice you've given me have always been a shining star to follow"