(CBS) The world's oldest twins are a pair of 102-year-old Scottish sisters, Guinness World Records announced Tuesday.
Meet Edith Ritchie and Evelyn "Evie" Middleton. They were born on a farm near Newburgh, Scotland, on November 15, 1909. The sisters are fraternal twins but their mother always dressed them the same from an early age.
The women, who were born at a time when Mark Twain and Florence Nightingale were still alive, have always remained close and and currently live together in Aberdeenshire, Scotland. Neither has ever left the U.K. to travel.
Evelyn had four children, 12 grandchildren, 26 great-grandchildren and three great-great grandchildren, while Edith had four children, nine grandchildren, 21 great grandchildren, and three-great-great grandchildren, according to Guinness.
What's the secret to their longevity? When asked, Edith said "Simple living, hard work and a good husband," according to a Guinness written statement.
Of course, other factors may have contributed.
"They've clearly benefitted from good genes, and a solid life-long friendship that only twins can truly understand," Guinness World Records Editor-in-Chief Craig Glenday said in the statement.
Nobody knows for sure what lead to the twins' impressive longevity, but research suggests happiness and family go a long way. A November 2011 British study in the Proceedings of the National Academy of Sciences showed happy people were 35 percent less likely to die an early death,
Dr. Howard S. Friedman, professor of psychology at the University of California at Riverside and co-author of The Longevity Project, toldlast year that simply being involved with friends, family, or co-workers is very effective at promoting a long life, and retirees who move away from their lifelong peers are more likely to die early.
A healthy lifestyle also might help lead to a long life. Afound that women who exercised at least 30 minutes a day, avoided smoking and obesity, and stuck to a heart-healthy Mediterranean diet, lived on average 15 years longer than women who met none of those criteria.