Earnhardt Jr. on Monday wrote that he was “glad her suffering has ended” so his mother could be “at peace.”
“She would be in tears of happiness over the words of support and remembrance she’s been shown today. Our family appreciates it as well. She will live in our hearts forever,” the 44-year-old race car driver tweeted.
JR Motorsports announced Jackson’s death in a news release on Monday. The release didn’t indicate the type of cancer. Jackson had worked for the company as an accounting specialist since 2004.
“Her sarcastic musings and straightforward approach injected a brand of humor at JR Motorsports that became part of its fabric as it grew into a full-time NASCAR racing operation in 2006 and a championship-winning organization in 2014,” the team said.
Jackson was the daughter of NASCAR fabricator Robert Gee, who built cars for various racers including the late Dale Earnhardt. Jackson married Earnhardt Sr. in 1972 and had two children, Earnhardt Jr. and Kelley Earnhardt Miller.
The couple eventually separated and, in 1985, Jackson went on to remarry Willie Jackson, a firefighter. Jackson is survived by her husband, two children, a stepdaughter, six grandchildren and two brothers.
In 2001, Earnhardt Sr. died from injuries sustained in a car wreck in a last-lap collision during the 43rd Daytona 500 in Daytona Beach, Fla. He was 49.
The Associated Press contributed to this report.