Most people see their 60s and 70s as a time to relax and enjoy life a little more.
But thousands of Kiwi grandparents have to step up and raise their grandchildren.
The bond Kiwi grandma Julie Herbert shares with grandson Ryan can be described in one word - special.
At first, Ms Herbert and her husband didn't know they had a grandson. They found out after a phone call telling them Ryan was in hospital. The eight-month-old baby had been "shaken" by someone outside the family.
The effects are certain to leave serious disabilities.
"We would go in daily to see him, and fell madly in love with him," Ms Herbert told Newshub.
"He was the image of his father, who is my son... and I just desperately wanted to him to be right again."
She was told Ryan would spend the rest of his life in a room. But after deciding to take care of Ryan, now 16, she was determined to change his fate.
"We never left him by himself. He was always stimulated, and this is the result we have now, which is... amazing."
Ryan can now walk, talk a little bit and even play the drums.
The Herberts' situation is one faced by at least 7000 Kiwi grandparents. They're being supported by the Grandparents Raising Grandchildren Trust. It buys things like school uniforms for kids like Ryan, and even pays for his swimming lessons.
It's now receiving a boost from Kiwi actor Bruce Hopkins.
"I had planned to raise $50,000," he told Newshub.
"But now I've decided on $100,000, and that will go toward helping a network of volunteers across the country."
Hopkins started walking the length of the country on Sunday to raise the money. He's hoping to give back to grandparents like Ms Herbert.