no color, just cream and white with carefully considered floral decorations each with a meaning. >> i learned very much from her. she has chosen the flowers. for example, the rose symbolizes happiness. the oak and acorn symbolizes strength and endurance. and we have a long list. a lot of these are actually within the architecture of buckingham palace. and sweet william, we haven't met sweet william yet. we will be. >> for william, he is working on his own cake as well in a tradition here at buckingham palace, he's going to have a groom's cake. guess what? it's made of chocolate cookies. the bridge tea biscuits mixed with chocolate into a cake mix that william has grown up with. >> it's once in a lifetime opportunity. absolutely delighted.