(CNN) -- Friendship is not defined by the length of time two people share together. One defining moment is all it takes for two individuals to call each other friends. Cory Monteith's life, short as it was, taught me that lesson. His death, sudden as it was, taught me that lesson. Coroner: Mix of heroin and alcohol killed 'Glee' star The defining moment of our friendship happened the third time I joined the cast of "Glee" for yet another memorable shooting experience as Sunshine Corazon. At the set, Cory was cool. Like his character Finn Hudson, Cory was so cool that everything seemed alright with him.
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Singer and actress Charice recalls her friendship with Cory Monteith on the set of "Glee"
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Charice: "Like his character Finn Hudson, Cory was so cool"
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"My body felt cold when I learned about his death," writes Charice
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The actress asks for Cory's fans to unite and celebrate his life and talents
But Cory came to the rescue, just in time, with his sweet greeting: "Happy birthday, @placeholder!"