The father of Patrick Alford Jr. — who disappeared in 2010 as a 7-year-old from his foster home — was shot in the head during a home invasion in Brooklyn, sources said yesterday.

Patrick Alford Sr., 29, exchanged gunfire with the armed teen punk who tried to barge into his Blake Avenue apartment in East New York at about 4:15 p.m. on Monday and steal 30 baggies of marijuana, sources said. He’s in a medically induced coma.