CEDAR RAPIDS — The Martinko family lived without answers for 39 Christmases.“Shock, anguish and horror” permeated the family them they first learned that 18-year-old Michelle Martinko was killed Dec. 19, 1979, John Stonebraker, her brother-in-law, said Friday in a videotaped victim impact statement.Decades after the death, he had a voice in the first-degree murder sentencing of Jerry Burns, 66, of Manchester.