Back when I was planning my wedding, I remembered reading that you could invite the President to your wedding and he would send back a letter of congratulations in return. So I did that and President Obama sent me a really nice card in the mail. 
sorry for the blurry photo!
When Adele was born, I also sent her birth announcement to the White House and just last week got a nice card back! I’m putting this in her Baby Book for sure! 
If anyone is interested in getting a keepsake like this, you can mail a wedding invitation or birth announcement to:
White House Greetings Office
Room 39
Washington, DC 20500
Good luck!
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