Richard Roderiquez, 16, was found dead and his mother and four siblings were found wounded inside a home in an unincorporated area of San Bernardino on Wednesday.
The father, Ian Roderiquez, has been charged with murder, attempted murder and torture.
On Sunday, friends, some of whom had known the teen since elementary school, gathered outside the family home.
They called him "Candyman" because he sold candy to help support his family.
Police described the scene as "horrific."
The mother is hospitalized in critical condition.