Daniela Ruah Pens Heartwarming Birthday Message to Daughter Sierra

NCIS star Daniela Ruah is celebrating a big day for her youngest kiddo!

Her daughter, Sierra, whom she shares with husband David Paul Olsen, celebrated her seventh birthday yesterday, Sept. 4, and Ruah had the most heartwarming message in honor of the occasion.

"We could not be more in love and proud of this kid," she wrote on Instagram. "Our youngest cub turned 7 today and we had a weekend of celebration and love. May you continue to work really hard at everything you do and may life smile at you always ???? Happy birthday to this incredible little girl that we’re lucky to call ours, and raise ??????."

She repeated the message, which accompanied a pair of sweet family photos, in Portuguese.

In the first snap, Sierra wore a floral, long-sleeved bodysuit as she leaned into her mother's side, the two smiling brightly at one another. In the second, she clutched her dad's hand as they walked away from the camera, her nine-year-old brother River leaning down to hug her as they strolled.

The kids started second and fourth grade last week, joining the legions of celebrity kids celebrating their first days of school in recent days.

Jessica Simpson sent her three kids off with a wholesome photoshoot featuring the family pup, while Khloe Kardashian struggled to hold it together as True headed off to her first day of kindergarten. Today's Craig Melvin sent his son and daughter off to fourth and first grade, respectively, while his colleague Hoda Kotb's daughters are preparing to head back soon with fresh new haircuts.

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