His parents confirmed to ABC News their son's death was possibly due to COVID-19 after he experienced symptoms of the virus.
News of his death sent shockwaves across the community that had come to know him and his family.
"It's very, very shocking, saddening, paralyzing," said Nicole Weinstein of Claremont.
Weinstein's daughter attended elementary and El Roble Intermediate School with Maxx and his twin brother Leo. The three were set to start the 8th grade in September.
"The minute I heard, it was like a huge bright light had been extinguished. He had so much charisma, so much positive energy. He was class president last year," said Weinstein.
The Cheng family says Maxx became ill back on July 4, but a COVID-19 test came back negative.
They said they thought he was getting better after his fever broke, his coughs slowed and he was breathing easier.
A GoFundMe account for Maxx describes him as a talented debater, math-lete and swimmer with dreams of going to the Olympics.
"I feel like Maxx was one of ours, he was one of our children, one of Claremont's finest and we all are very sad. Whether we knew him or didn't, he's one of our children, he's one of our youth," said Weinstein.
The family tells ABC News the coroner is performing more tests to determine if their son's death was caused by COVID-19.
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