The Mongrel Mob member shot and killed in Whanganui on Tuesday morning was a 27-year-old father of two.
Kevin "Kastro" Ratana was celebrating his oldest son's seventh birthday the day before he died, Stuff reports.
His cousin Shan Albert said Ratana was a "great father". Ratana had two sons, aged 7 and 3.
"Yes, he was a gang member, but that was just one side of him. It was family first," she said.
"Even though his family background wasn't that great, nothing could stop him from doing what he wanted to do."
Albert said Ratana grew up in Whanganui, although he had also lived in Hastings and Australia.
She also said he was well known around town for his association with the Mongrel Mob.
"Everyone knew who he was, but he put on a front."
Ratana's shooter was still on the loose on Wednesday morning. Police said a scene examination was underway and cordons would likely be lifted late on Wednesday or on Thursday.