A family of four from Massachusetts who were killed when a bus crashed into multiple vehicles in Virginia were traveling to a wedding with a carload of homemade desserts for the celebration. The family wedding will go forward Sunday in South Carolina, but it also will be a time to mourn the loss of Dmitri and Ecaterina Doncev and their two children, Emily and Mark, a relative said Saturday. “A son, a father — the whole family — everyone that has been dear to us,” Carolina Bublik said. The Doncevs were killed when a motorcoach caused a chain-reaction crash with vehicles that had slowed down for a work zone on Interstate 95 in Stafford County around 2:35 a.m. Friday, authorities said. The bus struck a Suburban, which then hit an Acura carrying the Doncev family, police said. Priscilla Mafalda, 25, of Worcester, Massachusetts, was in the Chevrolet SUV and also died. More people were treated for injuries, including one who was in critical condition, though most were discharged, Mary Washington Healthcare said.…