“American manners are different than British manners.” — Ingrid Seward

The Middletons and the Windsors might seem at first glance to be worlds apart. Kate certainly shows no sign of adopting the horsey, doggy lifestyle beloved of her grandmother-in-law. But the Queen admires how well Kate has embraced royal life, combining it cheerfully with duty and motherhood.

The path of royal romance has never been smooth; Princess Margaret was unable to marry the man she loved because it meant renouncing her royal status, yet her uncle, the Duke of Windsor, gave up an empire for Wallis Simpson.

When Prince Andrew tired of romancing a pretty dancer and turned his attentions to Koo Stark, he instructed the Buckingham Palace switchboard not to put her through when she rang.

The enormity of the Duke and Duchess of Cambridge's global influence is daunting, especially for Kate, whose look is admired, copied, and analysed everywhere.