"Together they got John out of the water," he said.
A formal identification process has been conducted to confirm the identity.
"We believe it is John Wakelin," Mr Lexmond said.
The family were advised immediately after the discovery.
Close family friend Russell Holmes says finding John was a "massive relief", for the immediate family, the boy's wider family and friends.
"John has been returned to them and that will certainly assist them with the grieving process."
Funeral arrangements are being finalised today.
"The family will make an announcement tomorrow on when the two boys will be farewelled," Mr Holmes said.
Mr Lexmond says finding the missing teenager was also a massive relief for all those involved in the search and for many more people in the Gisborne community.
"It cannot take away the shock of the tragedy for the family, but everyone is hugely relieved John has been found."
A rahui put in place on the Makorori and Wainui beaches at the weekend will remain in place until this weekend.
Gisborne's Campion College was mourning the loss of two special and well-liked students who were very gentle in nature, said principal Paul McGuinness.
Paul and John Wakelin both attended the college, and John was to finish his schooling there this year. Paul left the school several years ago to work with his father.
"They were both very gentle and quiet boys, and very genuine in their willingness to help other people," Mr McGuinness said.
"Paul returned to the school from time to time after he left to help other students out. He was that sort of person."
Mr McGuinness said they were the sorts of students who formed strong friendships with others.
"The boys themselves were very close and it is good news for the family that they have both now been found."
The college held a prayer service yesterday for the brothers on the first day back at school.
"All the families of students at the school were notified of our intention to do that. We let everyone know about the tragedy at the weekend."
Mr Lexmond reinterated the boys' father Chris Wakelin's comments about the assistance and support provided to the family and the searchers since Saturday.
"It is amazing.
"It is great to see that support at this trying time for the family," Sergeant Lexmond says.
"The community's compassion and kindness comes out in tragic times like this."