Kim flew out of Paris on Monday morning, and was reunited with her family in New York City. Kanye West met her at the airport
, and the source tells ET that she "spent the entire day" with her 3-year-old daughter, North, and her 9-month-old son, Saint. "She's very emotional. The scariest part for her throughout this experience is the fact that it could have been a lot worse, and she couldn’t imagine what that would have been like for her children," says the source. "The kids have no idea what’s going on, thankfully."