Disbelief as Doctor Reveals How Second-Born Twin Is Technically the Eldest

A junior doctor with the U.K.’s National Health Service has gone viral after discussing a phenomenon that can occur during the end of daylight saving time.

On October 28, TikTok user @dr_arthur_ posted a clip in which he shared an anecdote he had heard about twins born in the U.K. on the last Sunday in October—when clocks go back an hour.

According to the doctor, he heard about the case from a midwife he’d worked with, who had about 20 years of experience and was present for the delivery.

“A mother who was having twins had given birth at 1:50 [a.m.] to the first twin, and the second twin came out half an hour later, which should, obviously, be about 2:20 [a.m.],” he said in the video. “But because the clocks went back, it was 1:20. This means that although the first twin was born before the second twin, legally, it is the younger twin.”

Newsweek contacted @dr_arthur_ for comment via TikTok. We could not verify the details of the case.

When daylight saving time ends, clocks are adjusted backward by one hour, creating a repeated time window. As birth records are tied to legal time, the time change allows the confusing scenario of a younger twin being older on paper. The doctor in the viral clip described such an event as “very rare.”

Eight years ago, ABC News reported that a couple from Massachusetts experienced this phenomenon.

In the U.S., daylight saving time ends on the first Sunday in November, and on November 6, 2016, Emily and Seth Peterson welcomed twin boys at Cape Cod Hospital.

Samuel, weighing 5 pounds, 13 ounces, was born at 1:39 a.m., just before the clocks turned back to end daylight saving time.

Ronan, born 31 minutes later at 5 pounds, 14 ounces, was born at 1:10 a.m.—which would have been 2:10 a.m. on a different night. As a result, although Ronan was born after Samuel, he is legally the older twin.

The TikTok video has received 1.7 million views, more than 140,000 likes and hundreds of comments, with viewers sharing their own experiences of giving birth in the final hour of daylight saving time.

One user described what happened when her son was born an hour after the clocks changed, writing, “On my notes, the labor was 8 hours, but really it was 9. Like they cheated me of my extra hour of labor.”

Other users marveled at the intricacies of timekeeping and legal records. “The crime novel based on inheritance basically writes itself,” one wrote.

Another added, “And don’t even get me started on how that would affect your astrological birth chart!”