Steven Ercolino's relatives say he was a warm and witty member of a tight-knit family.
His sister, Maria Rashford, delivered the eulogy during the Wednesday morning service at Our Lady of Sorrows Parish in White Plains.
She says her brother's death on Friday left "a hole in the family."
Police say the 41-year-old was killed by a former co-worker who blamed him for being laid off last year.
The gunman, Jeffrey Johnson, was killed by police moments later after he pointed his gun at two officers.
Nine bystanders were wounded by stray police bullets when the officers opened fire.
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