Ever since the Queen Mother achieved the status of Britain's favorite granny, the first week of August has been reserved for celebrating her birthday. But this year, for the first time, the oldest royal shared the fanfare with the youngest. While the Queen Mum turned a robust 89 on Aug. 4, bonny Princess Beatrice turned four days later. Two of the most popular royals, the pair didn't celebrate together. And by week's end it was Bea, or rather, some of her gifts, that were drawing the attention—not all of it flattering.

The Queen Mum opted for an adults-only luncheon, but her special day wasn't completely child free. After being serenaded by a lone bagpiper on the grounds of Clarence House, her London residence, then by a crowd of 3,000 that sang "Happy Birthday to You" three times, the Queen Mum was presented with a bouquet of flowers by Barry Millard, 7, a schoolboy, who was smartly dressed in the uniform of the Irish Guards. "I think she's brilliant, better than any pop star," he said, beaming.

Shortly after noon members of the royal family arrived for lunch. Queen Elizabeth came without Prince Philip, Charles and Diana left William and Harry at home, and Andrew and Fergie were Bealess. Princess Margaret's two adult children, Viscount Linley and Lady Sarah Armstrong-Jones, also attended, but Margaret, who had lunched with her mother two days earlier, sent only her regrets.

After dining on salmon in the garden, the Duke and Duchess of York, with Queen Elizabeth in tow, picked up baby Bea and set off on the royal yacht Britannia for a 10-day cruise of the Western Isles. Although she has made few public appearances, Bea behaved regally—waving to the crowd, graciously accepting a birthday bear from the navigational officer's daughter and, later in the week, riding out her first royal flap.

On Bea's birthday, a front-page story in the newspaper Today accused Andrew and Fergie of giving the princess an expensive—£2,044 ($3,270)—rocking horse made of mahogany from the endangered Brazilian rain forests. Both the Friends of the Earth and the Green Party joined the chorus of criticism, but in the end their faces were red. While the rocking horse is stabled in the nursery, it was given to Bea a year ago by Chestnuts, the family-owned business that designed and carved the toy. The horse was made just before Beatrice was born and "installed in the nursery ages ago," said Christina Crittenden of Chestnuts. "So there is no question of the Duke and Duchess of York ordering and buying it, or choosing a special type of timber," Buckingham Palace was quick to add.

On a happier note, Bea's gift from Uncle Prince Charles, who joined the family on the yacht over the weekend, was approved with flying colors. He presented his niece with a tricycle shaped like an airplane, and he and her parents took turns pushing the birthday girl around the decks. Bea also thrilled to the sight of a family of gray seals that swam alongside the ship as it neared the Isle of Man.

By staying behind in London, the Queen Mum was able to avoid all the horseplay. She faced a more pleasant kind of music at a performance of Anything Goes. And at her age, she should know.

—Mary H.J. Farrell, Jonathan Cooper and Laura Sanderson Healy in London