Diana Leann Hart of Hill City, South Dakota, age 55, passed away peacefully and surrounded by family at home on December 6, 2025.

She was born on January 2, 1970, in Hutchinson, Kansas to Theodore A. and Carol June Stoughton. She was a graduate of Buhler High School, Hutchinson Community College, and Black Hills State University with a degree in education and an endorsement as a teacher of English as a Second Language.

During the summer of 1989 while working at Yellowstone National Park, she met Rodney "Rod" Hart. The two fell in love and were married on November 3, 1990, in Hutchinson. For 35 years of marriage, they lived at Yellowstone then at Mt. Rushmore National Memorial, raising their children as Rod worked for the National Park Service.

She was proud of the 19 years she spent as a 2nd grade teacher at the Rockyford School in the Oglala Lakota County School District. She was passionate about learning, understanding and teaching the language and culture of the Lakota Sioux to her students. During a ceremony celebrating her work at the school, she was honored to be adopted into the Lakota Sioux family receiving the name, Tewahila Ota Win, which in English means "Loved by many."

She will be remembered as a loving and committed wife, mother, grandmother, daughter, sister, and friend.

Diana is survived by her husband Rod, daughter Cassidy, son Ivan and his wife Amanda with their two sons, Tristin and Beckett, father Ted and his wife Betty, sisters Angel and her husband Steve, Julie and her husband Jay, Rachel and her husband John, brother Zachary and his wife Juliana, brother-in-law Alan, sister-in-law Michelle, and seven nieces and nephews. She was preceded in death by her mother Carol, brother Joshua, father-in-law Ivan, and mother-in-law Lee.

A memorial service will take place on Saturday, January 3 at 10:00 a.m. at the Little White Church in Hill City.