EMBED >More News Videos The Action Cam was there as First Lady Melania Trump arrived in Philadelphia on October 17, 2018.

EMBED >More News Videos Melania Trump's plane forced to return. Matt O'Donnell reports during Action News Mornings on October 17, 2018.

EMBED >More News Videos Raw video from first lady Melania Trump's plane after it was forced to return to Joint Base Andrews on its way to Philadelphia on October 17, 2018.

PHILADELPHIA (WPVI) -- First lady Melania Trump toured a hospital's neonatal care unit Wednesday to learn about the treatment given to newborns suffering from opioid withdrawal, after she was initially delayed by mechanical issues on her plane.Her flight was forced to return to a Washington-area military base because of smoke in the cabin, and she took a different plane to make the trip to Philadelphia.Mrs. Trump spoke briefly at a conference at Thomas Jefferson University Hospital on newborns who have been exposed to opioids while in the womb. The hospital has provided care to mothers with opioid use disorder and their newborn children for more than 45 years.She was introduced by Health and Human Services Secretary Alex Azar, who said the Trump administration's plan to fight the opioid epidemic was "comprehensive and driven by the best science we've got."She began her remarks by saying "sorry for a little delay."Mrs. Trump said there are few things harder than seeing a newborn suffering from opioid withdrawal, and that she wants to shine a light on the issue."As the caretakers of the next generation, it is our responsibility to protect our most valuable and vulnerable, our children," she said.After touring Jefferson's neonatal care until, the first lady was also going to visit with mothers who are in addiction treatment in a program that allows them to have their children with them.According to reporters traveling with the first lady, the original flight was in the air about 10 minutes when smoke filled the cabin. A member of the crew handed out damp washcloths for passengers to put over their mouths, and Secret Service agents rushed to the front of the plane.It was not immediately clear what caused the problem on the aircraft, a Boeing C-32A identified as "Bright Star."The visit was one of a number of stops planned to promote her "Be Best" campaign, which focuses on issues affecting children, including the importance of healthy pregnancies.------