Mango Island is part of the Ha'apai Island group and was one of the closest to the volcano when it erupted, producing a tsunami the Tongan government says generated waves up to 15 metres high.
Aucklander Mote Pahulu was born on Nomuka Island and grew up on neighbouring Mango Island.
"We're absolutely devastated. Not only have we lost a relative, a very close relative, but everything else on the little island is gone," he tells Newshub.
"It was a beautiful little island, it was a little paradise."