When it comes to raising daughters, Bruce Willis has a sixth sense.

So after his eldest daughter Rumer Willis gave birth to a baby girl of her own, Louetta Isley Thomas Willis, the new grandfather and the now-13-month-old quickly formed an unbreakable bond.

"Lou is just starting to walk a little bit and she was walking over to [Bruce] and it was so sweet," Rumer told Today's Hoda Kotb May 29. "It's so nice because I feel like my dad is just, he's a girl dad through and through. It almost unlocks that kind of little kid, girl dad thing. He's so sweet with her."

Rumer, who shares her daughter with partner Derek Richard Thomas, posted a heartwarming photo of Bruce holding the toddler last month as part of a first birthday tribute to her little one. It marked a rare glimpse at the Die Hard actor, who stepped away from acting in 2022 and has been battling frontotemporal dementia.

And seeing her mom Demi Moore and dad—who also share daughters Scout Willis, 32, and Tallulah Willis, 30—become grandparents, has been a magical experience for Rumer. 

"Honestly, seeing them with her, it just, it almost unlocks all of these childhood memories because being a grandparent, I think, is the best. They have all of the love and joy without any of the responsibilities," Rumer said about her parents' relationship with Lou. "They get to just spoil her."

That blended family spoiling her also includes Bruce's daughters Mabel Willis, 12, and Evelyn Willis, 10, whom he shares with wife Emma Heming Willis.

In fact, Emma shared a heartfelt message alongside a peek at the full family gathering to celebrate Rumer's daughter

"Family and friends gathered to celebrate sweet Louetta's first birthday," she wrote on Instagram. "What a blessing she is and to see @rumerwillis blossom into motherhood so effortlessly has truly done something to my heart."

Look back at Bruce's family moments over the years...

"Oh Daddio, to be loved by you is such a gift," Rumer Willis wrote in an Instagram tribute to her father in March 2024. "You are the funniest, most tender, charming, out of this world silly talented and magical papa. Looking through these photos this morning I am just filled with the deepest gratitude that we chose to spend this life together. I am your first baby and man sometimes I wish I could be tiny enough to just cozy up on your chest again and laugh and cuddle you."

She continued, "I love you so deep in my bones I don’t know how my muscles hold them. You are the greatest papa I could ever hope for. Thank you for your generosity, your silliness and heart. Lou loves you so big. Happy Birthday Daddio."

Love is a beautiful thing," the actor's wife Emma Heming Willis wrote on Instagram, almost exactly one year after his family announced his frontotemporal dementia diagnosis. "Wishing you all a Happy Valentine’s Day."

In February 2024, Demi Moore shared this pic of her ex-husband with the youngest of the three daughters they share together, writing, "Showering our @buuski with love today on her 30th birthday."

In November 2023, the actor celebrated his first Thanksgiving since being diagnosed with frontotemporal dementia earlier that year. His wife Emma shared this photo from Bruce's 68th birthday party from March.

"I’m grateful and thankful to know this kind of love," she wrote. "Wishing you all a Happy Thanksgiving."

Bruce Willis stepped out with Emma to celebrate the release of Demi's 2019 memoir Inside Out. He is joined by his three daughters with the G.I. Jane actress, Rumer Willis, Scout Willis and Tallulah Willis.

Bruce and Emma appear on a hike with their daughters Evelyn Willis and Mabel Willis.

The actor posed with his ex-wife and their daughters Rumer and Tallulah backstage at his Comedy Central roast in 2018.

Bruce became a grandpa in April 2023 when Rumer welcomed a baby girl named Louetta.

The entire family got together to celebrate the birth of Rumer's baby.

Bruce had two special vistors when he starred in Broadway's Misery in 2016.

The family showed up in full force to support Rumer's 2015 Broadway debut as Roxie Hart in Chicago.

"I put my camera on a ladder, set the timer, and crossed my fingers," Emma captioned this family Christmas photo. "Now that’s 2020 for you."

Bruce took his three oldest daughters to the Over the Hedge premiere in 2006.

The dad of five shared a sweet moment with daughter Mabel.

Tallulah, Scout and Rumer joined their dad at a Bruce Willis Charity Foundation in 2005.

The family celebrated Rumer's Dancing With the Stars win with Val Chmerkovskiy.

"What a privilege it is every day to be your daughter," Rumer captioned this throwback photo. "I love you so much. You are the coolest cat in town."

Emma rang in her 43rd birthday in 2021 with Bruce and their daughters, as well as Rumer and Demi.

The family spent Christmas 2022 together.

Bruce was joined by mom Marlene and his three oldest daughters when he received a star on the Hollywood Walk of Fame in 2006.

The action star dressed up with Mabel and Evelyn on Halloween 2021.

Tallulah jokingly captioned this photo of herself and dad Bruce making silly faces, "high drama club."

Evelyn and Mabel hit the slopes during a family ski trip.

The family, including Demi's then-husband Ashton Kutcher, stepped out to watch Rumer in 2008's The House Bunny.

Bruce and Emma took their kids to Walt Disney World in 2017.

"First time performing in a play for these two!" Emma wrote on Instagram 2018. "Mabel played Molly and Evelyn as Sandy in an Off-off-off-off-off-off Broadway [winking emoji] production of Annie. The whole cast and production was stellar—Mom and Dad couldn’t be prouder."

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