An excerpt from Nancy’s book, Discover Your Family History Online It started at the Fort Rosecrans National Cemetery in San Diego, California. My sister and I were at the cemetery, taking photos to fulfill a FindaGrave.com request. But – as always – we couldn’t resist driving into the older section of the cemetery and walking back through the stones. An old tombstone caught our eye. The inscription was to Sgt. John Gallagher of Battery B, 4th U.S. Artillery. A veteran…