Neither boy can be identified due to court suppression because of their age.
Yesterday, the accused killer's grandmother said the incident was too emotive for the family to talk about.
"There's too much grief going on," she told the Herald at her Ellerslie home.
From behind her closed screen door, she added: "We are just so sad for the Indian family."
Last night, the Kumar family held a public viewing for the dairy owner considered one of the nicest shopkeepers in Henderson.
The family have paid tribute to the West Auckland man as "a perfect husband, a perfect dad and a perfect son", while community members spoken to by the Herald in Henderson this week laid flowers outside his dairy and praised his friendliness and generosity.
His funeral will be held in Wiri at 2pm today.
The family of the 12-year-old boy jointly charged with the aggravated robbery of Mr Kumar would make no comment when they were approached at their Henderson home.
Friends and family of both accused have expressed support on Facebook for the boys, who remain in custody ahead of future court appearances.
A family member of the 13-year-old posted on her page that her world had been "torn apart" by the stabbing.
"I love you so f***** much my baby bro," she posted on Tuesday.
"Our family will make it through this, we are strong enough. We have to stick together."
Later, on Tuesday night, she added: "Many thanks to all family and friends for your support we really need it and appreciate it during this hard time that we are going through."
