In her darkest hour, he was at his Finest.

A mother who lost her two young sons in a deadly Queens fire found invaluable help and support from an NYPD cop — who helped her organize her children’s burial and fly her mother to her side.

“I just felt a huge void, emptiness,” said NYPD Detective Patrick Blanc, 47, of seeing the bodies of tragic 6-year-old Andrew Kavanagh and 11-year-old John Kavanagh being pulled from the Oct. 6 house blaze in St. Albans.

Blanc said he was off-duty, driving nearby, when he heard about the fire on the radio and rushed to the home to find it engulfed in flames. The boys had been home alone while their mother, Marie Policard, 42, was working at a local health clinic.

Her only children were found on a staircase, where they had tried to flee the inferno.

“That’s the only thing she ever worked for, the only thing she talked about, her two boys,” Policard’s coworker, Vincent Davis, told The Post at the time.

Blanc returned to the scene the next day on his own time.

The cop and his girlfriend, Valerie Fequiere, along with their 13-month-old son, Patrick Jr., approached Policard.

“I told her, ‘I can’t say everything is going to be OK, because it’s not OK,” Blanc recalled. “I told her if there was anything she needed to give me a call.”

The next day, the phone rang.

The devastated Policard, a Haitian immigrant, was now overwhelmed by the cost and logistics of a funeral.

Central Robbery Inspector Vincent DiDonato gave Blanc the go-ahead to reach out to people and groups for help.

The NYPD Community Affairs Bureau and City Councilman Daneek Miller pitched in. A local business owner, who wishes to remain anonymous, paid for the funeral.

But one thing was still missing: During Policard’s darkest hour, she lacked the comforting presence of her own mother.

Grandma Aurose Pierre Louis was mourning miles away in Haiti.

Blanc, his girlfriend and Miller found discounted airline tickets through Delta. Then the cop boarded a plane to Port Au Prince to pick the elderly woman up and escort her to New York City.

“With everything my family was going through, this was very good support,” Policard said.

“I didn’t expect anything like this, and I am really appreciative of all that the community has done.”