Lily Collins Celebrates 'First Birthday as a Mama' as She Reflects on 'Magical Year' — 'I Truly Couldn't Be Happier'

Lily Collins' 36th birthday will forever be a standout in her memory.

The Emily in Paris actress celebrated her big day with a pair of family photos posted to her Instagram grid on Tuesday, March 18.

The sweet images showed her beaming as she stood next to husband Charlie McDowell holding their baby daughter Tove Jane, whose birth the couple announced on Jan. 31.

"First birthday as a mama and I truly couldn’t be happier or imagine it being any more special," Collins wrote in her caption. "What a magical year it’s been and what a beautiful year I’m stepping into."

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She concluded, "Grateful doesn’t even begin to express how I feel ... "

McDowell, 41, shared his own tribute to his wife for her birthday, posting a black-and-white photo to his Instagram grid that showed Collins peering down lovingly at their baby girl.

"Happy birthday to my stunning wife," wrote the filmmaker. "You are patient, kind, hilarious, and so loving to our beautiful Tove. Both she and I are so lucky to have you in our lives. I love you forever. Happiest birthday mama."

"Love you so much and couldn’t have imagined a more perfect way to welcome this new year. ❤️," Collins wrote in a comment. "Just the most special with our little family ❤️."

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McDowell's mom Mary Steenburgen also left love for her daughter-in-law in the comments section of her son's tribute to Collins.

"We all love you so much, Lily. Xo ❤️," wrote the Oscar-winning actress, 72.

Collins and McDowell welcomed baby Tove via surrogate earlier this year, announcing the happy news in a joint Instagram post on Jan. 31.

“Welcome to the center of our world Tove Jane McDowell," the proud parents captioned their announcement, which featured a photo of the newborn in a knit bonnet.

They added, "Words will never express our endless gratitude for our incredible surrogate and everyone who helped us along the way. We love you to the moon and back again."