Blake Lively and Ryan Reynolds are expecting their first baby together.
At the bottom of the post there is a photo of Blake proudly rubbing her – already sizeable – bump.
Blake's letter read:
"Preserve at its core is about family. Family is the single word our founder, Blake built this home on.
"We have something for men, for women, for the old, but we realized, we don't have anything for the new. With family on our mind, we looked to the origin of it all-to the women in our lives who are right there, at that special moment; at the creation of family.
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"Today we celebrate them. With food to fill their tummies (as if that needs more filling), presents to soothe their tired (and swollen) soles, toys to warm their baby's souls, projects to provoke them, and decorations to inspire creativity and merriment in all.
"We had too much fun with this. Because there's so much to share, we break up our first ever Preserve Celebration into multiple parts. In the upcoming days we will bring even more treats and fun. The entire next month will be sprinkled with highlights for women in this exciting chapter of their lives.
"Congratulations to all the expecting mothers out there. And thank you for being a part of our Preserve family."
This is the first baby for Blake and Ryan, who got hitched in 2012.
Ryan was previously married to Scarlett Johansson, who gave birth to her first baby, Rose, earlier this year.