CEDAR RAPIDS — Growing up, Denise Marti-Wyatt and Lisa Marti remember their grandmother talking about the pain of being separated as a child from her sister.Ruth Moss, their grandmother, was only 5 when an explosion at the Douglas Starch Works factory in Cedar Rapids killed her father, Mike Schultz. Her mother already had died of influenza and the May 22, 1919, blast left Ruth and her two siblings orphans.They were separated — Ruth and her brother were raised by one family, while her sister, who later died as a teen, was sent to another house.