Jaden, who goes to Dilworth School in Auckland, and Jemma, from Strathallan School in Karaka, proudly donned a constellation of medals their dad had earned during his military service. They included medals from East Timor, Bosnia and Afghanistan.
"Dad's been to a lot of countries and done a lot of service in lots of different places," Mrs Grant said afterwards.
The family said they laid a wreath every Anzac Day for the families of the fallen as well as Corporal Grant.
"These are the times when it actually comes back. You get a lump in your throat and a tear in your eye and you realise this is all happening because he's not here. And that's sad, that's really sad.
"And he can't see my beautiful children growing up and being amazing, like they are. They make me so proud."
She added, laughing: "They're just amazing kids, when they behave, eh?
"Willie and I, we're good friends, so we just stick together," Mrs Grant said.
Alex Hopkins, 6, laid a posy of red, white and pink roses at the memorial, a reminder of the final bouquet his father Corporal Mathew "Hoppy" Hopkins sent his wife, Victoria.
Mr Hopkins was born in Christchurch in 1987 but soon after moved to Australia. He served with the 7th Battalion Royal Australian Regiment and was killed in March 2009 while on patrol near Kakarak, 350km west of Kabul.
The Australian memorial was created as part of the new Pukeahu National War Memorial and is a reciprocal gesture to the NZ Memorial on Anzac Parade in Canberra.
Australian Prime Minister Tony Abbott and Prime Minister John Key spoke at the ceremony.