A fire department helicopter dropped divers who found Lazar 15 minutes after he fell in.
"When we need them, they're there. And certainly that child needed them. The grandfather needed them. And they were there. And I want to commend them and congratulate them because they certainly exemplify why the Chicago Fire Department is regarded as the best in the world," said Ald. Isaac Carothers, police and fire committee chairman.
Mayor Daley congratulated the heroes.
Doctors say Lazar has recovered and will lead a normal life.