"The first thing I thought of was I'd love somebody to help me make a vege garden. It's something I've wanted to do but never got it under way."
Willis - who has been married to her husband, Rob, for nearly 20 years - has devoted her life to her children, aged 2-26. She is days away from becoming a grandmother for the third time.
She has always tried to make a difference in her Cannons Creek community and credits her children as her inspiration.
"I do what I can for my children and that gets you involved in stuff like running a playgroup for the community because you feel like there's nothing for mums to connect together.
"I know there are tonnes of great mums who are very busy so I'm feeling very humbled."
Eldest daughter Crystal Southey nominated her mother, saying she worked tirelessly for others, including new and young mums in the community, sat on school boards and was a mother to anyone who walked through her door.
Warehouse spokeswoman Julia Morton said Willis was chosen because she embodied what it meant to help make New Zealand families flourish.
Willis said the thing that was most special about motherhood was discovering her children's personalities and watching them develop.
"As they grow into adults I've loved watching them mature and come out of the teenage years and become good adults."
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