"PS To the many, many people who have wished our family well, sent knitted goods and passed on a piece of wisdom about parenthood over the past year — thank you. It truly takes a village (and someone in said village may get a call if I don't sort this cake!)."
Her admission of vulnerability prompted an enormous response, with parents flocking to share their own cake-making nightmares.
"I made the cat for Tilly's first and she face planted in it with excitement that it was 'all hers'," commented Instagram user Carly Flynn. "Such a milestone — well done you guys."
Sally Biddick said her daughter's first birthday cake was supposed to be La La from the Teletubbies but "resembled a deranged teddy bear ... however I have progressed over the years and even managed Hogwarts by her 15th."
Another commenter offered a tip in case her efforts turned out pear-shaped. "If the cake doesn't look like the picture in the book, make a new story for it," she said. "I once made a Thomas Tank Engine cake that turned out to be 'Thomas down the mine'."
Kathryn D said it was a "parenting rite of passage, struggling through your first birthday cake from the WW birthday cake book."
Ardern and partner Clarke Gayford's daughter Neve Te Aroha was born on June 22 last year. The NZ PM was the first elected world leader to take maternity leave and only the second — after Pakistan's Benazir Bhutto 28 years ago — to have a child while in office.
New Zealand's "first baby" then again made history when she turned up at the UN General Assembly in New York at the age of three months.
Gayford also tweeted a picture of the infant's UN diplomatic photo ID, adding: "I wish I could have captured the startled look on a Japanese delegation inside UN yesterday who walked into a meeting room in the middle of a nappy change. Great yarn for her 21st."
Asked by NBC's Today Show what was harder — taking a 3-month-old on a 17-hour flight or running the country, Ms Ardern joked: "It felt at the time on par, I have to say!"
Ardern again won praise from around the world for her decisive and empathetic response to the Christchurch shootings. Wearing a black hijab, she embraced and talked with the Muslim community after the shocking mass killing — and moved quickly to tighten the nation's gun laws.
It was the same week that Neve reached nine months and started crawling, and Gayford marked it with a poignant post.
"For her 9 month birthday today we received the gift of crawling," he wrote.
"Her mum got her the gift of having a safer country to grow up in."
This article was first published on news.com.au.
