ABC News' Carolyn Durand reports:

Speculation fueled by Prince William himself that a sibling to his only child, Prince George, was on the way has been apparently put to rest, thanks to a few sips of wine.

Both William, 31, and his wife, Kate Middleton, 32, visited a New Zealand vineyard Sunday, part of the royal family's 19-day trip Down Under, and both enjoyed a tasting of pinot noir.

Kate's sips of wine, suggesting that she's not pregnant, came just days after Prince William told a woman who made a gift for 8-month-old Prince George, the couple's first child, that she might need to make another one.

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Also quelling the rumor mill was the wild boat ride Kate took this weekend, with the whitewater jet boat she rode topping speeds of 50 mph.

The Duke and Duchess of Cambridge, as the couple is formally known, continued the competitive and athletic spirit they've maintained throughout the trip by also showing off their skills on the cricket field in Christchurch, despite being dressed in heels and a skirt (Kate) and a suit and tie (William).

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William accidentally sailed a ball near his wife's head, and got a warning wag of a finger from Kate in response.

The couple's more formal attire on the cricket field came because they had earlier paid their respects at a ceremony in Christchurch remembering the 185 who died in an earthquake that demolished much of the city three years ago.

The royals have perfected the "hongi" - the traditional New Zealand greeting of a nose kiss - during their 10 days in the country but will now head to Australia next, where they will finish their tour Down Under.