A trip to one's spouse's grandmother's house isn't a big deal for most, but most of our grandmas aren't monarchs, nor do they live in palaces.
On Friday, Kate Middleton and Queen Elizabeth II went on a one-on-one tour of the exhibitions for the summer opening of Buckingham Palace.
The exhibits prominently feature the April 29 royal wedding.
Among the items on display are Kate Middleton's Alexander McQueen wedding dress, her Cartier tiara, and the three-foot-tall wedding cake.
Here's the Queen and Duchess taking it in ...