I am searching for information on an American family that lived in San Luis Potosi in the early 1900's. Robert Louis Stevenson, a train engineer, was living and working in the area with his wife (name unknown) and his son, Homer Eads Stevenson. Homer was born in San Luis Potosi about 1903. Robert was killed in a train wreck in Mexico. His wife also died (cause unknown), leaving Homer an orphan. I have found a 1920 census record for Homer, age 17, living in San Antonio with a grandmother named Nora Smith. I don't know if she could be an adoptive grandparent or a biological grandparent. I would truly appreciate any ideas on where I might look for information on a train wreck or about Americans living in Mexico during that time period.