Queens woman was ‘the boss’ of home where son-in-law killed her

A quiet Queens neighborhood was pierced with screams just moments before a drunk and disturbed man allegedly stabbed his mother-in-law to death and knifed her teen son, neighbors said.

Shi Quijin, 50, described as “the boss” of the house, was killed when the 27-year-old suspect launched the attack inside the Smart Street home and set a mattress on fire.

“I heard a man screaming, not words, just ‘aaahh.’ Then I heard a woman say, ‘Call an ambulance.’ In English. I was surprised, because they don’t speak the English over there,” a neighbor who witnessed the aftermath of the tragedy told The Post, declining to provide her name.

Three bloodied people were rushed to to NewYork Presbyterian Hospital, where the gravely wounded mother-in-law succumbed to her injuries.

Quijin’s 17-year-old son, who was stabbed in the face and armpit, was listed in stable condition.

Their attacker was also hospitalized and is in police custody. He has not been publicly identified as no charges have been brought and the probe continues.

According to the neighbor, Quijin was a dedicated mother who spent hours of her time working on the facade of her house and tending to her garden.

“I was very impressed with her, I think her husband was a construction worker. 
And when they brought that property, [about 13 years ago] it was like a small house there. They built all that. And I watched her build it, with a couple of other women. They did most of the work. 
They tore that old house down. Physically, they did. She was the boss,” the neighbor said.

“It’s very sad.”

Police say that Quijin’s 27-year-old son-in-law had been drinking before he knifed her and her 17-year-old son multiple times in the home, slit his own wrists and set the mattress ablaze.

One of the victims ran outside screaming, catching the attention of a nearby Port Authority cop who rendered first aid and called authorities.

The suspect has no prior arrests or run-ins with the law, but is reportedly in the throes of a divorce.

It’s not clear whether he or his estranged wife lived at the Smart Street home, though several members of the extended family appeared to be residents.

Guqing Zhang, 20, and his sister Rouxin Lin, 16, were both in the basement when they heard a bang and screaming — only to go upstairs and find their wounded, bleeding aunt and cousin.

“Everyone was panicking… and I went to open the door and I went in (the room) and  I saw my aunt on the floor, not moving. And then they said there was a guy with a knife inside,” Zhang told The Post.

Martha Flores Vasquez, the founder of Community Prevention Alternatives and a clinical psychologist, theorized that the 27-year-old accused killer was likely experiencing a mental crisis.

“My thoughts on what transpired is that somebody is decompensated, mental health decompensation, and probably off his medication,” she said, explaining that decompensated is another term for unstable.

“If you see something, you have to say something. If a neighbor sees that somebody looks unstable, just by the look in their face, you have to call the police and report it.”