The informal meeting with 10 parents was held at Government House in Wellington. According to local media, all of the babies were born within a week or two of Prince George, who was born last July.
William and Kate started their three-week tour of New Zealand and Australia on Monday.
The royal couple plan to spend the next few weeks enjoying a wine tasting at a local vineyard, meeting with "The Lord of the Rings" director Peter Jackson, going on a jet boat ride and visiting the New Zealand city of Christchurch, which was devastated by an earthquake in 2011.