As part of their Easter vacation, Princes William and Harry followed in the bootprints of countless British adventurers by heading to East Africa on safari. The royal party-about 15 in all-started on March 21 at Kenya's luxurious Kiwayu Safari Village. Then it was off with Prince Charles (who joined them on March 28) to the Selous Fame Preserve in Tanzania-and possibly back to the Aberdare Mountains in Kenya, where Charles once traveled with the late mystic Sir Laurens van der Post, his mentor. "He has alwas wanted to share a safari with his sons," says Peter Archer, royal correspondent for Britain's Press Association. "He has always taken the boys on holidays where they have to wear a blazer or tweed jacket. This breaks the mold." In Africa, too, Wills should be safe from a mystery thief who has been snatching the name tags from his underwear at Eton. The suspicion is that, given his heartthrob status, HRH's BVDs are being targeted by souvenir hunters.