Pamela Rauseo, 37, performs CPR on her nephew, 5-month-old Sebastian de la Cruz, after pulling her SUV over on the side of a Miami highway on Feb. 20, 2014. (Al Diaz/The Miami Herald/AP Photo)

The mother of a baby who had to be resuscitated by the side of the road said the incident may have led doctors to the cause of the infant's distress.

Sebastian De La Cruz made headlines last month when a news photographer captured dramatic photos of the infant being resuscitated by his aunt by the side of a Miami highway.

After being resuscitated twice, Sebastian was initially listed in stable condition at a Miami hospital before being released. His mother Paola Vargas told reporters at a news conference on Wednesday that Sebastian had cysts removed from his trachea to help with his breathing, according to the Miami Herald.

Pamela Rauseo, Vargas' sister who was photographed resuscitating De La Cruz, said doctors performed "invasive" tests find the reason for Sebastian's respiratory distress.

"We finally got to the root of what was causing his condition and his difficulty breathing. Had it not been for that incident the doctors would not have performed such an invasive procedure," Rauseo told reporters. "That is the only way we would have been able to determine what he had."

See the Dramatic Moment When a Woman Pulled Over to Give Infant Nephew CPR

Vargas said she was grateful for her sister's actions every day.

"I thank God, I thank my sister every day," Vargas told reporters. "When I wake up and I see my baby I'm so happy. "

Baby Sebastian de la Cruz with his aunt Pamela Rauseo at the Hachar Law Firm in Miami Lakes, March 5, 2014. (Al Diaz/The Miami Herald/AP Photo)

Sebastian, only 5 months old, was born premature and had respiratory problems. Rauseo jumped into action when she realized her nephew wasn't breathing and started CPR even though her only training was seven years ago.

"I don't know how I remembered what to do. … I just knew I couldn't let him die," she told ABC News.

ABC News' Dan Good contributed to this report.