The first blaze broke out around 2:00 a.m. in a house on Paisley Drive.
Crews arrived to heavy flames and battled for about an hour before extinguishing the blaze.
After cleaning up the scene, firefighters left about 3:40 a.m., officials say.
Around 5:20 a.m., firefighters were called back to the scene, only to return to find flames had engulfed the entire house.
There were no injuries reported but two people have been left homeless from the blaze.
The cause of the fire is under investigation by the Delaware State Fire Marshal's office.