Ayla said: "I was shocked to learn I had been chosen. I am so excited with this opportunity to experience something new and I am especially looking forward to testing the new toys."
The Warehouse chief executive Simon Turner said it had become the country's most sought after role.
"It's clear from the calibre of entries that Kiwi kids take their toys very seriously.
"We're thrilled Ayla and Kyle are on board and we're looking forward to their unique perspective on what's cool in toys and games - it can be a great source of inspiration for Kiwi parents who aren't sure what to buy," he said.
The official toy testers would receive up to $200 worth of toys to review each month and a Huawei Mediapad to record their reviews.
The videos they create would also be shared on The Warehouse's YouTube channel for people to watch nationwide and around the world.
As well as monthly toy reviews, the toy testers would be involved in the company's Halloween and Christmas festivities - where they would be first to try out new costumes and decorations before they hit shelves.
