Mother plans to honor 9-year-old son killed by his father in San Jose

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Tuesday, September 2, 2025
Mother plans to honor 9-year-old son killed by his father in SJ

SAN JOSE, Calif. (KGO) -- For the first time, ABC7 News is hearing from the mother of a 9-year-old boy who was stabbed to death by his father in San Jose in July.

Sandra Rencontre plans to remember her son in a way the community can benefit.

"It's a whole other life," Rencontre said. "I never imagined that I would have to live this life without him."

It's a grieving mother's dilemma, after her 9-year-old son was murdered by his own father.

Rencontre is unsure how to go forward, but knows her son, James, would want her to be happy.

RELATED: San Jose police shoot man suspected of stabbing, killing 9-year-old son

San Jose police officers shot and killed a man armed with a knife at a public park Sunday afternoon after he allegedly stabbed his own son to death.

"He was a jokester and just super kind and compassionate," Rencontre said. "One of his schoolmates wrote, even though he knew he didn't need to be everybody's friend, he was still kind and tried to be everybody's friend."

Rencontre spoke with us about her special boy and the events that transpired at Cataldi Park in San Jose in July, for the first time since that day.

When asked what her thoughts were when she got that call and found out the horrific news, Rencontre said: "It was crazy. I mean, I spoke to them throughout the day. I didn't realize that there could be anything wrong until it was already too late."

Police say the father, Mateusz Dzierbun, called 911 to report that his son was badly stabbed, describing the suspect as a different person.

Officers said when they arrived, Dzierbun charged at them with a knife, which is when they shot and killed him.

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Rencontre said she and Dzierbun cohabitated and raised James together, and she's still shocked by how much Dzierbun's mental state had deteriorated.

"I mean, you can see it when you look backwards," Rencontre said. "But in it, you wouldn't of, there's no way you would've noticed."

Rencontre hopes to leave a lasting mark that represents her son the right way at the park where he died.

San Jose City Councilmember David Cohen, Mayor Matt Mahan and the community have raised enough money for a memorial bench.

It's a way to remember James for how he lived and not how he died.

"This tragedy didn't just affect me and my family, it affected an entire neighborhood, an entire school district and the whole community," Rencontre said.

"It's something that, I think, has really weighed on all of us and, of course most of all, James' mother," Mayor Mahan said. "And so, to the extent that we can give her a little bit of comfort and solace and just show her that the community is thinking about her that she's not alone, I think that matters and if we absolutely want to do that."

The rest of the more than $12,000 raised via GoFundMe will go towards James' favorite library and elementary school - to give back to the community still devastated by James' loss.

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