In 1992, Raymond Ratima knifed and bludgeoned to death his pregnant sister-in-law Nicola Ferguson, 20, her partner Bevan Tepu, 21, their child Stephen, 3, Nicola's brother Phillip Ferguson Jnr, 14, and his own children Piripi, 7, Barney, 5 and Stacey 2.
He then lay in wait in his in-laws' darkened home in Judds Rd for his wife, Toni, and Phillip and Tubby Ferguson to return home, where he attacked his father-in-law with a softball bat.
But Mr Ferguson stood his ground and fought back as the others rushed to neighbours and police were alerted.
Ratima later pleaded guilty to seven murders, an attempted murder and the killing of an unborn child, and was sentenced to the then-mandatory life sentence.
Since then he has come up for parole several times, his bid for freedom each time been fiercely opposed by family of his victims.
Mr McGregor said he would not be attending this week's parole hearing as "nothing had changed since last time''.
The whanau also doubts Ratima is the writer of the letter sent to the television journalist.
Mr McGregor said Ratima "wouldn't have the intelligence to know what those words mean''.
In his letter to the One News reporter, Ratima turned down a request to be at the parole board hearing, saying he did not want an advocate, did not seek a "balanced representation'' of his life but wanted his whanau and those of his victims to "heal as best as they can in their lifetimes''.
He wrote: "Regretfully, I took the lives of seven whanau members, members of my whanau continue today to suffer mentally, emotionally and physically for their loved ones.''
The New Zealand Parole Board said prisoners had the right to veto a person's attendance at a hearing, as does the board itself.
Ratima's appearance before the board this week will result in a reserved decision.