She was Randall's wife, and always told him he belongs with his family, and should stop running off into the wild. When Randall ignored her and went on a hike, she died with the rest of the family without Randall when the bombs fell in 2077.
On October 29th, Randall dedicated one of his diary entries to her, even though he knew she was dead. It described what happened during the air raid, and how she was right.
Char Clark is mentioned only in Honest Hearts.