Yahaira Vega was born with a rare disorder that prevents the tiny hairlike structures in her airway from removing germs and pollutants.

"You know that large drink size from McDonald's, you know, dollar cokes? I could fill one of those with phlegm in a day," Yahaira said.

On top of that, Yahaira"s organs in her chest and abdomen were reversed.

"So, your heart is typically on the left side, but now it's on the right side. The right lung is on the left side, but the left lung is on the right side," Thoracic Surgeon Dr. Ankit Bharat said.

Dennis Deer was also born with this rare genetic condition called Situs Inversus.

"I was getting progressively worse to the point where I couldn't even walk 10 steps without gasping for air," Deer said.

Both Dennis and Yahaira were the first two patients at Northwestern Medicine to receive double-lung transplants for Situs Inversus.

"When we take the old lungs out, now you have to put the normal, right lungs, from a normal person that's donating the organs, to fit into the cavity that's the mirror image," Dr. Bharat said.

When Dennis woke up from surgery, he knew it worked.

"Incredible. I'm still mesmerized by it," Deer said.

Now, both Dennis and Yaharia are back to living their normal lives.

"I don't take any days for granted now," Deer said.

Situs Inversus affects nearly one in every 10,000 people. Often, patients may not even know they have the condition until seeking health care for unrelated conditions.