The little boy who collapsed and died in his Bronx school cafeteria was a cheerful, respectful child, his former neighbors remembered Saturday.

Tyzavier Martin, 6, died Friday on his second day at PS/MS 5 in Port Morris.

Investigators were still determining what caused the boy’s death, and whether it was connected with a throat-slash injury he’d suffered in April, allegedly at the hands of his mother, Shanice Martin, 24, who remains jailed.

The boy and his two-year-old sister, who Martin is also accused of slashing, were being cared for by other family members, the family’s former Bronx neighbors said Saturday.

“I can’t judge the mother,” said one ex-neighbor, Dalia Ayala, 48. “I never saw her do anything to her children — they were well-dressed, clean. The boy was so respectful.”

The family clearly needed more support, neighbors agreed. “They should have given her help,” one said of the mother.