Marge Sill, a longtime environmental activist known as the "Mother of Nevada Wilderness," has died at the age of 92. Sill died at her Reno home Sunday shortly after falling ill, according to family members and leaders of Friends of Nevada Wilderness — one of the groups she founded. Sill joined the Sierra Club shortly after graduating from Cal-Berkeley in 1949 and became a leading voice behind congressional passage of The Wilderness Act in 1964. Sen. Harry Reid says every protected acre of Nevada, has Sill's fingerprints on it.