Credit: iansomerhalder/Instagram

Nikki Reed turns 29 years old today, and she definitely has a lot to celebrate.

Not only is the star pregnant with her and husband Ian Somerhalder's first child, but she also recently launched a new sustainable clothing line. However, the sweetest part about her special day is quite possibly Somerhalder's heart-melting tribute to his expectant wife, which he shared on Instagram alongside a photo gallery of their many romantic adventures together.

"Happy Birthday to the most amazing human I know... Today, we celebrate you," the actor wrote. "For an innumerable amount of reasons I couldn't even begin to describe, as all of those who know you and those who even don't know you, would agree. It's your day."

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Somerhalder continued: "The love and light you radiate to the world shines like a beacon for all to see. Its that love and light that guides me to the safe shores of home from the turbulent and sometimes treacherous waters of life. Thank you for your tireless pursuit of spreading good, being an instrument of change and seamlessly weaving the complex threads of our lives together into the warmest, softest and most magical blanket. Every day I get to watch you being you I'm constantly reminded of your beauty and prowess and how lucky I am to share this life with you. Love, Ian."

Cheesy? Sure. But these two seriously couldn't get any cuter.