I saw that the President of the United States will send congratulatory cards if requested. What about the Queen of England?
As long as the required applications are filled out with proper documentation (i.e. birth certificate or marriage certificate), a congratulatory message will be sent from the Queen, but only for the following birthdays and anniversaries:
Birthdays: 100th, 105th and then every year thereafter.
Wedding Anniversaries: 60th , 65th, 70th and then every year thereafter.
In addition, a message will only be sent to citizens of "Her Realms or UK Overseas Territories." Therefore, a citizen of the United States is not eligible. However, a Canadian citizen is eligible, as well as citizens from about 30 other countries such as Australia, New Zealand, Bahamas, and Gibraltar. See full list at the Royal Website, www.royal.gov.uk
The application can be downloaded from the Royal Website below, but not sent in until within 3 weeks of the event. The Queen's message could arrive up to 6 months after the birthday or anniversary date. See www.royal.gov.uk for more information.