The event had been tremendously overwhelming for the siblings' mother, friends said.
The Australian born siblings were described by family as "gentle, loving children with the biggest smiles and beautiful, sometimes shy personalities".
"Since Anatoria currently resides in Perth, her family has flown over to support her through this awful time," Miss Maniapoto said.
"As much as I and others would love to go and show our love, we aren't able to.
"Instead, we have organised a get-together for friends, family and the community so Anatoria can see that all of us back home love her and care."
Miss Maniapoto said the event was important for family who would not be able to farewell the siblings in Perth.
"Make some signs, bring the kids to play at the park and then join us close to the water on Paraparaumu Beach to let off balloons.
"Anyone is welcome and we hope people will spread the word."
¦A GoFundMe account has been set up for Zaraiyah and Andreas' family here.