Mr Thomson's 7-year-old twin daughters, Zarah and Alexis, are "gutted" that their team's jerseys are gone, particularly as the Thomson family were tasked with washing them after Alexis won "player of the day" a fortnight ago.
"[Those were] brand new jerseys - they'd only had seven games in them. Now they're back in their old jumpers, which aren't in Waitemata colours," Mr Thomson said.
It's not the best start in Northland for the family, who moved from West Auckland to Whangarei eight weeks ago.
Mr Thomson and his partner Elysa Schuster are converting a Spedding Rd house into a daycare centre, set to open later this year.
It was outside this house that the jerseys, in a supermarket chiller bag, along with rugby boots, a tablet, a laptop and GPS device, were stolen from Mr Thomson's unlocked car.
"We've lived in West Auckland for 38 years and we could leave our car unlocked [on our property] without anything being stolen," he said.
Despite this, the Thomson family aren't letting a few bad eggs ruin a good place.
"We've met a lot of good people up here," he says.
And he's hoping the good people of Whangarei will help him get the jerseys back.
"A few people have said to me, and I agree - 'you don't steal from kids'."
The jerseys can be dropped off, no questions asked, to the Northern Advocate office in Robert St or at the Whangarei police station.