The paediatrician, who gave up a national role with Plunket to return to clinical work in Hawkes Bay, was something of a surprise choice as commissioner in May last year, having supported "anti-smacking" legislation in a form which the National Party fought in Opposition.
There were also political murmurings about the Wellington-based role going part-time - something Wills insisted on so he could continue paediatric work at Hawkes Bay Hospital and reduce the impact on his wife Mary and their two teenage sons.
As Government MPs who defended the appointment noted, his reputation is for walking-the-talk: he was prominent in Hawkes Bay initiatives - including pre-school health checks and domestic violence intervention in hospitals - which were both rolled out nationally. In a region with some of the country's poorest families, they led to big reductions in hospital admissions of children for assault, neglect or maltreatment.
He is quick to credit the "extraordinarily talented" people around him for any successes. His drive to make a difference, he says, stems from community-minded parents (who still live across the road) and early tutelage by renowned Hawkes Bay paediatrician Dr David Barry.
Dr Wills has certainly brought a sense of purpose to his commissioner work: calling for a Children's Act and annual measurement of progress towards stated child health goals and establishing the experts' panel which has just made more than 70 recommendations.
Child poverty is just one of Wills' priorities for his five-year term but you get the feeling he won't allow the report to gather dust. "I know the Government is taking this seriously; they've got officials working on the recommendations now."