A long and happy marriage is something to be celebrated by friends and family alike, but a personal greeting from The President of The United States or from Her Majesty The Queen can prove to be the icing on the cake for many couples on their Wedding Anniversary.

It will come as no surprise that President Obama and Queen Elizabeth don't have the date of your relatives' anniversary pinned up on their wall planner, so it is up to the children, grandchildren, relatives or friends to notify them of the approaching date.

In the USA, requests for greetings cards from The President for 50th, 60th or 70th Wedding Anniversaries should be sent to: The Greetings Office, The White House, 1600 Pennsylvania Avenue, Washington, D.C. 20500. The White House is currently asking that requests are received at least six weeks in advance of the event and will send greetings to US citizens only. You can also apply through your congressman - In some instances this may be easier and you may be able to apply via your congressman's website.

The Queen will send greetings on a Diamond Wedding Anniversary to recognise 60 years of marriage. The Queen currently sends out more than 25,000 messages for Diamond Anniversaries each year, although the number of messages shot up by more than 20% between 2004 and 2005, reflecting the number of marriages that took place as soldiers returned at the end of World War II sixty years before.

The delivery of Wedding Anniversary messages from The Queen is arranged by the Anniversaries Office, part of the Private Secretary's Office in the Royal Household, based at Buckingham Palace. The address is: The Anniversaries Office, Buckingham Palace, London SW1A 1AA. A form is available that can be downloaded online to make the application process easier. A copy of the marriage certificate is required to confirm the names and date.The palace asks that applications are sent no sooner than three weeks before the event, but it may be worth having a look at the Buckingham Palace website for the latest update.

It is The Queen's custom only to send messages to citizens of the UK or UK Overseas Territories. Residents in Australia, Canada and New Zealand should apply directly to their Governor-General.

If you know of a couple who have a major Wedding Anniversary coming up, it's worth planning ahead, apply in secret, and then a message of congratulation from The President or The Queen is an unexpected and very welcome surprise.