A pair of identical twins who have never lived apart just celebrated their 100th birthdays—and they still can’t get enough of each other.

After a century of being attached at the hip, Mary Belle Roach and Mae Belle Powell from Symsonia, Kentucky, still dress alike, get their hair done together, and live with each other in their childhood home. They have even taken to sharing a bedroom in case one of them ever needs anything in the middle of the night.

‘We’re together all the time; we’ve never been separated,’ Mary told Today. ‘That’s all we know: to love each other.’ The sisters, who are still known as ‘The Wallace Twins’ because of their maiden names, were born in their hometown of Symsonia on March 25, 1916 in the midst of World War I.

Mary and Mae Belle were teenagers during the Great Depression, and Mary recalled how their family ‘had nothing’ at the time. Despite the financial hardships of the time, the two women were able to afford the $5 a semester tuition to attend Murray State College together.

As college student, the twins took advantage of their identical appearances and divvied up their time in the classroom based on their separate interests.

While Mary would go to gym class for her sister, who ‘can’t hit a ball to save her life’, Mae Belle would return the favor by doing her sister’s book reports.

The sisters even chose chose the same profession. After they married a pair of best friends that they had grown up with, they both took teaching jobs at Symsonia Elementary School where they made a $1 per day.

Mary and Mae Belle taught in classrooms that were right across the hall from each other, but after their husbands were drafted into World War II in the 1940s, they temporarily moved to Detroit to work in wartime factories.

‘Everything was real quiet; I remember how sad it was,’ Mary said of hearing about the attack on Pearl Harbor on December 7, 1941.

She will also never forget the Sunday after the first atomic bomb was dropped as she recalled how ‘you had to wait in line just to get into church.’

After the war ended, the sisters and their husband bought motor homes and traveled around the country.Over the course of their lifetimes, they have visited all 50 states, as well eight countries in Europe, together.

The women, who are both widows, continue to remain active despite their 100 years. They keep each other company at a nearby gym where they walked for 30 minutes each day, and every Friday they go to the hair salon dressed alike.

Mae Belle insisted that if she is not with her sister she is worried, and they both agree that they simply can’t get enough of each other.

‘I need her all the time,’ Mae Belle said. ‘We’ve had a wonderful, wonderful, wonderful life and still have it.’As for their secret to living living to 100, Mae Belle told Inside Edition its ‘good genes’, noting that their mother lived to be 97.  ‘We didn’t smoke cigarettes. We didn’t smoke that pot. We never drank beer,’ she added.