Barbara Walters recently asked President and First Lady Obama, "How do you keep the fire going?"
She asked the question earlier this month, during a wide-ranging interview that touched on marijuana legalization, the fiscal cliff, Robin Roberts and the Obamas' marriage. Watch the two respond to Walters' question in the preview above.
It is the fourth time that the Obamas have sat down with Walters. The interview will air on a special edition of "Nightline" on Friday, December 28. It was originally scheduled to air on December 14, but got a different air date when news of the tragic shooting in Newtown broke.