Olsen's wife, Kara, delivered the twins -- boy T.J. and girl Talbot -- via Ceasarian section Tuesday. Doctors told the couple prior to the birth that T.J. had hypoplastic left heart syndrome, a rare disease that sees a child born with an underdeveloped left ventricle and aorta. The condition strikes fewer than four in 10,000 babies born, the Charlotte (N.C.) Observer reported.
T.J. Olsen will undergo three surgeries in all before his third birthday to repair his heart, doctors said. The first operation is scheduled Thursday.
"He continues to be closely monitored by physicians and clinical staff during this very important period of time," Olsen said Wednesday via text message. "We appreciate the thoughts and prayers and respect for our family's privacy."
Panthers coach Ron Rivera was optimistic the child would make a full recovery, noting both the babies were roughly 8 pounds at birth.
"They were both big," Rivera said. "One was over 8 pounds. The other one was almost 8 pounds. Now T.J. is in the infant care unit, and they'll go from there. So far, so good. We'll keep them in our thoughts and prayers."
Notable deaths of 2014 [PHOTOS]