A 3-year-old boy was shot in the head inside his Brooklyn apartment early Saturday, cops and neighbors said.

The little boy, who neighbors identified as Terrell, miraculously survived when the bullet pierced his skull inside the E. 21st St. apartment in Flatbush about 3:30 a.m., cops said.

The child was rushed to Kings County Hospital, where he was listed in critical but stable condition.

Terrell was inside the second-floor apartment with a woman babysitter and another man when he was wounded.

It was not immediately clear if the child was hit by a round fired outside or inside the apartment, but detectives were quizzing the man who was with the boy when he was shot, sources said.

Neighbors said little Terrell, who was born prematurely, survived a dog attack several months ago.

“(His mother) had a pitbull and the dog attacked the baby,” said one neighbor, Jay Nichols, 36.

“He was just recovering from that. The dog bit him in the side. He had to wear a colostomy bag…He’s three years old. He shouldn’t have to live in these kind of conditions.”

Nichols said the resilient Terrell had a smile on his face during their last encounter a couple of weeks ago.

“He looked happy,” Nichols recalled.

“Like he was just getting over the dog bite. Now this…I’m p—ed off. He’s just a little kid.”

Jocelyn Harris, who lives a couple of floors up from Terrell’s family, said he often saw the boy with his mother.

“It’s a shame,” she said. “It’s hard to believe that it was this little child. I’d see him with his mother…She took care of him. They were always together around here.”

Read more: NY Daily News