A 66-year-old man with dementia was reunited with his family Friday after going missing nearly four days ago.

Jose “Che” Santiago was admitted to Jamaica Hospital Medical Center Thursday after being found knocking on doors in Queens.

Santiago, who is also diabetic, lives with his sister Maria. Santiago wandered off shortly after Maria had called for an ambulance Tuesday in response to his high blood sugar.

The 72nd Precinct set up a full command center as they searched for the senior, even enlisting aviation and the harbor squad.

The man has since spoken with his family but doesn't seem to remember where he's been the past few days.