Twin baby boys conjoined at the head were successfully separated Friday following a 16 hour surgery at Montefiore Medical Center in New York City. The 13-month-old brothers, Jadon and Anias McDonald, now have a chance at a more independent future.

Jadon was the first to exit the operating room after more than 16 hours of surgery, CNN reported. He was wheeled out on a stretcher at 7:40 a.m, He was followed by his brother Anias around 1 p.m. As of Friday afternoon, both boys are reunited with their family. According to the Facebook page of the twin’s mother, Nicole McDonald, Anias was in surgery for longer than his brother because his head incision had to be reopened.

Today was the fourth and final surgery for the boys. Three prior operations helped to slowly separate the boys' skull in order to lead up to today's successful procedure. The official separation occurred at 2:11 a.m., but it took additional time to ensure that the boys were recovered well enough to leave the operating room.

The operation was led by Dr. James Goodrich, who, according to CNN, is the leading expert on craniopagus surgery — operations separating twins conjoined by the skull. Over the last decade, Goodrich has performed five other craniopagus surgeries throughout the globe, including one just earlier this year performed in Saudi Arabia.

In the past, craniopagus surgeries often involved sacrificing the life of one twin to save the other, or losing both twins during or soon after the operations. Today’s successful procedure demonstrates a big step forward in craniopagus surgery, though its future is still uncertain. The next months will be critical in terms of the twins' recovery, according to the Facebook page.

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The Curious Life Of Conjoined Twins: How Sharing A Body Changes The Way They Think, Drive, And Date: Read Here