The Waverley crash was New Zealand's worst road disaster in 13 years.
Only the children's mother, Ani Nohi Nohi, survived. She is in a stable condition in Wellington Hospital's intensive care unit this morning, a spokeswoman said.
A family member said a phone was put to Nivek's ear in her hospital bed so her father and other relatives could speak to her.
The 8-year-old was now with her baby sister in heaven and the family was grieving the loss of their two "precious princesses".
Hospital staff told Nivek's family there was nothing more they could do to save her, as they scrambled to be by her bedside.
Joy Clark with her goddaughter, Nivek Madams, 8, who died in the horrific crash at Waverley yesterday.
Her father is serving a prison sentence and was phoned before life support was turned off. She was also given a blessing by a hospital pastor at her father's request.
"Nivek has been surrounded by her family since the crash and was baptised by Pastor Sonny of Waikato Hospital at her father's request," a family friend posted on a Givealittle page.
"Nivek & Shady were close sisters and part of a caring whānau, deeply loved by their friends & family. Their tragic passing has been devastating for everyone and we are grateful for the outpouring of support from the community.
"As the new cluster of Matariki stars for those who have left us were announced Nivek's little life slid away," the family wrote on the page.
Nivek's godmother, Joy Clark, yesterday flew from Whanganui to Hamilton to get to the little girl's hospital bedside in time.
