With plans for family time, work and romance during a three-week tour Down Under, Kate continues to refine the art of being a thoroughly modern princess. This week's issue of PEOPLE goes inside Kate's royal mom life raising nine-month-old Prince George. William, 31, and Kate, 32, "are so proud to be showing George around where they can," a friend tells PEOPLE. And yet, adds a Palace aide, "there's only a limited amount of things that a baby can do."

For Kate, the trip marks only her third international tour – and her first visit to Australia and New Zealand. Apart from a small number of carefully chosen engagements, she has mostly busied herself caring for George and overseeing renovations at the family's homes in London and Norfolk, as well as nesting at the Bucklebury home of her parents, Carole and Michael Middleton. "It's something she's always wanted to do," says William's private secretary, Miguel Head. "The breadth of things they're going to be seeing and the people they're going to be meeting makes her very enthusiastic. [William] is in no doubt that his wife will fall in love with New Zealand and Australia every bit as much as he did some years ago."

But it's their active, soon-to-be-toddler who will most keep them on their toes. With two new teeth and having just learned to crawl, "he will be at a very inquisitive age," says Sarah Dixon, a maternity nurse who has worked with friends of the royal couple. "He will enjoy being out and exploring new sights and sounds." Having just recently survived the sleepless newborn crying stage, "I think the sleep routine is going to be a massive issue for them" given the change in surroundings and time difference, says Dixon. "Baby food preparation is another thing to consider at this age," she says. "They will liaise closely with the chefs there because it's important that his food is prepared correctly. The logistics of traveling with a nine-month-old are pretty extensive, really!"

*Also in this week's People:*
Kirstie Alley: "I've Gained 30 Lbs… My Weakness Was Chicken And Noodles"
Exclusive - Duggars In Love : One's Courting, One's Engaged!
Exclusive - Amanda Bynes: How She's Really Doing

More stories are featured in the 4.21.14 issue of PEOPLE, on newsstands now.