Mary Bowerman

USA TODAY Network

Thirteen-month-old conjoined twins were successfully separated Friday after sixteen hours of surgery at a New York hospital, according to the twins' mother.

Nicole McDonald posted on Facebook early Friday, that the surgery was successful, but that her boys, Jadon and Anias, are still far from in the clear.

“I should feel so happy,” McDonald said in the post. “TWO SEPARATE BABIES!!!...and yet I ache with the uncertainty of the future. I didn't cry until the surgeon's left the room. I was barely able to even utter the words 'thank you' because of the pit that still sits heavy in my stomach. We are standing on the brink of a vast unknown."

The procedure was completed by James Goodrich, a surgeon at the Children’s Hospital at Montefiore Medical Center in the Bronx, CNN reported.

Goodrich has completed seven separation surgeries, and the twins’ surgery marks the 59th craniopagus separation surgery in the world, according to CNN. Craniopagus twins are conjoined at the head.

Nicole and her husband Christian made the decision to go through with the surgery despite the possibility that one or both of the twins may have brain damage, CNN reported.

According to Nicole’s post, the twins shared some brain tissue and “Anias really got rocked during the surgery.”

The twins will remain intubated for about a week, according to Nicole, who set up a GoFundMe to raise money for some of the medical costs.

“So we just took a huge leap of faith, but now we are back to taking baby steps,” Nicole said. “In fact, I'm pretty sure I'm still frozen in space and time...in the smiles of yesterday morning. I'll be hanging out there until I see those smiles again."

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