The Lykov family (Karp, his wife Akulina, and their two children, nine-year-old son Savin, and two-year-old daughter Natalia) fled their Russian home in 1936 when they experienced religious persecution and settled in the Siberian wilderness.  The couple had two more children, Agafia born 1944 (center in the photo below) and Dmitry born 1940. All have passed except for Agafia who continues to live in the family’s camp.

The Lykov family, Karp the father and his two daughters, Natalia on the right and Agafia. Photo was taken in 1978 when a team of geologists discovered them. Agafia was 34 years old here. She is the last surviving member.

Some articles:
For 40 Years, This Russian Family Was Cut Off From All Human Contact, Unaware of World War II, Smithsonian Magazine, 28 January 2013
Lost in Time: The Incredible Story of the Lykov Family of the Siberian Wilderness, History Defined

In 2013, a crew from Vice visited Agafia in the wilderness. She was 69 years old at the time. They created this short documentary:

Meet The Last Lykov, Vice 2013
Wikipedia: Lykov Family
Wikipedia: Agafia Lykov

Agafia, as far as I can tell, is still alive and living alone in the Siberian wilderness. She’s 78.

Agafia Lykov. Photo: Bored Panda