My hubby and I decided to tell our kids and my family this weekend, so we planned a geocaching trip up a beautiful local canyon. I had secretly created a treasure box filled with little toy babies, a newborn diaper and hat, and a note that read:
Congratulations on finding this cache! Your real treasure is a new baby coming to join our family due to arrive on March 9, 2012.
Then I secretly hid the box off the trail and marked its location with my GPS. After searching for some real geocaches I got the gps to point the way back to my secret treasure and no one knew it wasn't a real geocache until they found it and read the note and opened it up. My kids were so excited. My sisters figured it out first and it took my mom a long minute. She actually said, "Oh, someone put this together to announce it to their family". Then I smiled and laughed and she figured out that that someone was ME. 
Even though this is baby #6 for us they were all really supportive and I think it helped to tell them in such a special positive way. We made it so awkward last time and it felt awful. This was a lot of fun.
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