Ngarewa-Packer is of Ngāti Ruahine, Ngāruahine, and Ngā Rauru iwi. She is a descendant of Tutange Waionui of Ngati Ruanui, who fought alongside Titokowaru during the New Zealand Land Wars and claimed credit for killing Prussian mercenary Gustavus von Tempsky. Ngarewa-Packer was a nominee for the Taranaki Daily News person of the year in 2018.