The death notices for Bradley, 9, and Ellen, 6, Livingstone said their lives would be remembered at a "celebration of life" service.
It will be held at St Leonards School from 2pm. More details will be released on Wednesday.
"Bradley and Ellen were colourful and delightful children - please share in the celebration of their lives by displaying colour in whichever way you choose," the notice from their family said.
Instead of flowers, donations would be accepted for Women's Refuge at the service.
The family and school community wished to farewell the children without a media presence.
"We will miss your cheeky grins, huge cuddles, constant singing and sense of mischief," said another the death notice.
"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 hair styles were like no other and you will never be forgotten."
The children's father, Edward Livingstone, 51, was also found dead inside the St Leonards home on Wednesday night.
The scene examination finished on Saturday and police enquiries are continuing.
Meanwhile, tributes continue to flow in for the siblings.
A Facebook page called, 'RIP Bradley and Ellen Livingstone', has received more than 4200 likes.
"Two little angels taken far too soon... Leave messages of love, support, and farewells," the page says.
Hundreds of comments in support of Ms Webb and the children's family had been posted.
People from all over New Zealand, and several from abroad, have used the page to pay tribute.
St Leonards School principal Jo Wilson said support from the community and former pupils had been "overwhelming . . .which is just brilliant".
"Everybody is doing what they need to do. They are looking out for each other and they all know we are there, which makes it as easy as it can be."
School staff last week opened a bank account for donations to be made to Ms Webb and Mrs Wilson said about $3000 had been deposited into the account by yesterday afternoon.
Details can be found on the school's website: www.stleonardsdn.school.nz
