SHE HAD A MASTER’S DEGREE IN PSYCHOLOGY. NO ONE SAW THIS COMING.

Pamela Cisneros appeared to live a quiet, respectable life. But behind that image, her family says she had struggled with serious mental-health problems and relied on regular medication injections.

To people who knew Pamela Cisneros, she was an educated professional who appeared to be living an ordinary life in New York.

She had earned a master’s degree in psychology and worked on and off for an immigration attorney, according to her family.

But behind that composed image was a much more complicated personal history.

Cisneros, 49, had struggled with mental-health issues for years. Her father, Mario Cisneros, said she had been receiving monthly medication injections as part of her treatment.

Her brother also described her as someone who had appeared stable for several years while receiving the injections.

Then, according to her family, something changed.

“IT WAS LIKE A SWITCH”

Cisneros’ relatives say they began noticing a dramatic change in her behavior shortly before the Times Square incident.

Her brother, Peralta, told Gothamist that the family had become concerned after Cisneros missed a regular family gathering.

They tried calling her, and her mother spoke with her by phone on Saturday. Cisneros reportedly said she was fine.

But days later, her family would see her on television in connection with the shocking events in Times Square.

“It was like a switch,” her brother said, describing how suddenly different she seemed.

Her father also told ABC7 that Cisneros had been receiving monthly injections for a mental-health condition and appeared fine when he saw her the week before the incident.

He said she had never seemed like a violent person to him.

WHAT HAPPENED IN TIMES SQUARE?

On Aug. 31, police say Cisneros approached two strangers in the heart of Manhattan.

According to investigators, she pulled two knives from a shopping bag and attacked a 68-year-old man before attacking 32-year-old Erin Piacenti.

Piacenti, a Bank of America vice president and new mother, later died at Bellevue Hospital.

The older man survived and was hospitalized in stable condition.

Police then confronted Cisneros.

Authorities say she refused repeated commands to drop the knives and continued threatening officers. Attempts to stop her with Tasers were unsuccessful.

Officers ultimately fired their weapons, and Cisneros was taken to Bellevue Hospital, where she was pronounced dead.

The NYPD has said there is no indication that the incident was terrorism-related. An internal investigation into the police shooting is underway.

HER FAMILY HAD BEEN WORRIED

In the days following the incident, Cisneros’ relatives began describing a woman who was very different from the person strangers saw in Times Square.

Her family says she had struggled with her mental health and had been receiving treatment.

They also raised questions about whether something had changed with her treatment shortly before the incident.

But those family suspicions remain just that — suspicions.

There is currently no public evidence establishing that a missed injection or interruption in treatment directly caused what happened in Times Square.

Authorities have not announced a definitive motive.

A LIFE THAT LOOKED ORDINARY FROM THE OUTSIDE

Cisneros lived in Queens and maintained relationships with family members who said they regularly saw her.

Her brother described her as someone who had worked for an attorney and lived a relatively quiet life.

That makes the events of Aug. 31 even harder for those who knew her to comprehend.

For years, relatives say, they had seen a woman who appeared to be doing better.

Then, seemingly within days, everything changed.

QUESTIONS THAT REMAIN

The Times Square incident has raised difficult questions about mental-health treatment, warning signs and whether anything could have been done differently before the tragedy unfolded.

But investigators still have to determine what was happening inside Cisneros’ life in the days leading up to the incident.

Her family’s account provides important context — but it does not, by itself, establish why she acted as she allegedly did.

For now, one thing remains clear:

The woman her family knew and the person seen in Times Square appeared to be separated by a dramatic and deeply troubling change — and investigators are still trying to understand why.

The investigation remains ongoing.