The wedding of royal cousins in Tonga this week has sparked controversy in New Zealand, with some Tongan New Zealanders opposing the union.
Crown Prince Tupouto'a 'Ulukalala is to be married to Sinaitakala Fakafanua on Thursday.
An Auckland Tongan community leader, Will Ilolahia says he is worried about the dangers of such close relatives marrying.
Mr Ilolahia says he agrees with the view expressed by Princess Frederica Tuita, who has called for the two royals to marry outside the family.
But he also says the wedding will be good for the Tongan economy and public morale during tough political times.
An Auckland-based Tongan lawyer, Kahu Baron-Afeaki, says in Tonga it is traditional for nobility to marry each other in order to keep the royal bloodline strong.
But he says there is nothing to stop Tongan royalty marrying outside of Tonga.