Every time Dave and Diane Gamble think about giving up the stewardship of City of Refuge for pregnant women, along comes someone like Melissa Renae Argetsinger.Pregnant at 17, Melissa said she was unable to stay with her family in Carson City and wouldn't stay with her baby's father.So, she turned up at City of Refuge to prepare for the arrival of Caden Charles Lee Hillman who was born Aug. 21 at Carson-Tahoe Hospital.From Belize to Battle Mountain, pregnant girls and women have found their way to City of Refuge for the past 14 years.The youngest mom was 13, the oldest …