Hundreds of people are expected to attend Saturday afternoon's service for the two Dunedin children killed by their father.
The death notices for Bradley and Ellen Livingstone said their lives would be remembered at a "celebration of life" service.
The service would be held at St Leonards School from 2pm and hundreds of people were expected, Gillions funeral services managing director Keith Gillions said.
The service would be held at the 180-person capacity school hall, and would be limited to family members, school pupils and their parents.
A large marquee and screen would be erected outside for those wanting to pay their respects, he said.
Dunedin businesses had offered their services, and Lions members would assist.
The death notice from the family noted "Bradley and Ellen were colourful and delightful children - please share in the celebration of their lives by displaying colour in whichever way you choose".
Instead of flowers, donations would be accepted at the service for Women's Refuge.
"We will miss your cheeky grins, huge cuddles, constant singing and sense of mischief," another death notice said.
"Bradley, you were the protector. You were always looking out for Ellen and were an amazing big brother. You have a gentle, caring soul and we will miss you dearly.
"Ellen, your infectious grin and beautiful singing would fill the room and make us smile. Your fashion sense and hairstyles were like no other and you will never be forgotten."
More than $6960 has been raised to help the children's mother, Katharine Webb.
Donations can still be made to the ANZ bank account (06-0909-0401308-00), under the name St Leonards School board of trustees.