They were a picture-perfect family.
In this heartbreaking recent photo obtained by The Post, doting Brooklyn mom Qiaozhen Li, 37, poses with her children: Amy, 7; Linda, 9; William, 1, and Kevin, 5 — blissfully unaware of the horrific fate that was about to befall them.
The five were slaughtered Saturday by a man whom Li and her husband took in off the streets as an act of charity: the dad’s cousin, Mingdong Chen, authorities said.
Chen, 25, stabbed each of the five to death with a butcher knife, slicing off some of Li’s fingers as she tried to defend herself and decapitating two of the children — including the baby, police said.
The lazy, transient loser was jealous because the beautiful family “had too much,’’ police sources have said.
He also may have been still stewing over being duped by a thieving Chinatown girlfriend, according to neighborhood gambling buddy Erdong Chen, no relation.
“A friend introduced him to the girlfriend a few years ago for the purpose of marriage,,” said Erdong Chen, 37, and Mingdong claimed he paid a $70,000 dowry to her family.
“We can save $30,000 a year by working every day,’’ Erdong noted.
But the girl ran off with the dough, Erdong Chen said.
“My girlfriend, I can’t believe she left with my money. I want to kill her,” Mingdong seethed, according to Erdong — who said he last saw Mingdong on Friday.
“He didn’t seem good in the head, agitated,” Erdong said.
He said the flat-broke younger man had been taking heat from his older cousin, Yi Lin Zhuo, for gambling and smoking. When Zhuo returned to his family’s home after the killings, the stricken father ran out of the house shouting, “Murder! Murder!’’ said Erdong, who was on the street at the time.
Mingdong Chen didn’t even have the humanity to say he was sorry after the slayings — and was only worried about himself when he got caught, authorities said.
“I know I am done,” Chen whined to his cousin’s sister and brother-in-law as they helped block him from fleeing the Sunset Park apartment after the grisly killings.
A law-enforcement source said Chen still appeared “indifferent” even during his confession. “He never said, ‘I’m sorry they’re gone’ or anything like that,” the source said.
The suspect was ordered held without bail on charges of first- and second-degree murder Monday.
Meanwhile, Zhuo was described as a devoted family man who worked around the clock as a cook at a Chinese restaurant to care for them.
“He would sleep upstairs here. … He work six days a week and go home one day a week to be with his family,” said Jian Guo Lin, owner of Best Wok in Rosedale, Queens.
Other tenants in the building where the tragic family lived said they plan to move as soon as possible.
“Feeling is bad,” said upstairs neighbor and taxi driver Yun Wang, 40.
At PS 105, Linda’s fourth-grade classmate Becky Shi, 9, recalled the tragic victim. “I’m really going to miss her a lot.”
“She lent me pencils when I needed them. She was so generous and shared everything,” Becky recalled.
Additional reporting by Elizabeth Hagen, Joshua Tanzer and Frank Rosario