"Diablo" had surgery for gunshot wounds at the University of Pennsylvania after the shooting on November 11th.
On Monday, his surgeon said the dog had developed pneumonnia.
However, doctors say Diablo is up and walking. He remains in the intensive care unit.
The shooting happened as police responded to a domestic dispute at the Chateau Orleans apartment complex, located near Philadelphia Pike and Shipley Road in Brandywine Hundred, Delaware.
Police say the suspect, Eric Weit, 34, threatened to kill his girlfriend. Diablo was shot as police tried to apprehend him.
Weit was then shot by police. He was flown to Christiana Hospital where he underwent surgery