Nicole Richie is happy to be a babysitter anytime. 

The star of the upcoming Don't Tell Mom The Babysitter's Dead remake—which premieres in theaters April 12—gave an inside scoop into her family's newest addition: her brother-in-law Benji Madden and Cameron Diaz's baby boy Cardinal.

"The cutest," Nicole told E! News of her baby nephew at the April 1 premiere of her new movie. "The absolute cutest."

And with Nicole's sister Sofia Richie also expecting her first child with husband Elliot Grainge—for whom Nicole feels "so excited I can't even stand it—her family's baby boom has the 42-year-old wondering whether she might want another child in her future. 

"Today I do not," Nicole, who shares kids Harlow, 16, and Sparrow, 14 with husband Joel Madden, said. "But ask me next week. I might feel left out, you never know."

 Cameron and Benji—who are also parents to 4-year-old daughter Raddix—shared the happy news of Cardinal's arrival on March 22.

"He is awesome and we are all so happy he is here," they captioned their joint Instagram post. "For the kids safety and privacy we won't be posting any pictures- but he's really cute. We are feeling so blessed and grateful."

In the years since she and Benji welcomed Raddix, Cameron had taken a step away from her career in Hollywood in order to spend more time with her family. In fact, the rom-com queen didn't take on any projects after 2014 until signing on for Back in Action, which also stars Jamie Foxx, which began filming in 2022. 

It was a career move that the Holiday star never regrets. 

"When you're doing something that you know," she told Kevin Hart in 2021, "and you've done well and you know how it works—and it's consumed your whole life for so long—it's kind of a nice thing to kind of go, 'You know what? Let me just step back for a second, take a look at what the whole picture looks like for me, and what are the things that I could do better and be more engaged with that would make me feel more whole?'"

And one of the things Cameron wanted to engage with was her growing family. 

"It's just a different time in my life now," she shared in an interview with Yahoo Finance that same year. "Now I'm here and this is the most fulfilling thing that I've ever done in my life. [To] have a family and be married and have our little nucleus of a family. It's just completely the best thing. So, I can't give...I don't have what it takes to give making a movie what it needs to be made. All of my energy is here."

- Reporting by Will Marfuggi

And for more 2024 celebrity babies, keep reading. 

Big Time Rush member Kendall and his wife Mica announced that they have welcomed their first child together, a baby girl named Maple.

The couple shared the news in a joint Instagram post March 22, posting photo of Maple as well as one of Kendall and Mica posing with their baby girl.

The Love is Blind and Bachelorette alums welcomed their son, Heath Orion Horstmann, in March.

"Our lives are brighter, fuller, and forever better," they wrote in their announcement. "Thank you for all of the love and well wishes, Heath has so many people who love him. We're parents!"

Katie Couric became a grandmother after her eldest daughter, Ellie Monahan, welcomed her first baby with her husband, a son named John Albert.

"Mom and Dad (Ellie and Mark) are over the moon (it was a full moon)," she wrote on Instagram March 24. "I am thrilled to have my first grandchild, Carrie can't wait to be a cool Aunt and Molner is enjoying handing out cigars. We feel so blessed."

There's something about this family, as the Good Charlotte rocker and the Charlie's Angels alum welcomed their second child—a baby boy named Cardinal Madden.

"He is awesome," they share in a joint Instagram post on March 22, "and We are all so happy he is here!"

The “Titanium” artist and Adonai actress shared that they welcomed their first baby together, Cyan.

“Love is in the air,” David and Jessica wrote in a joint Instagram post March 17. “Welcome Cyan.”

The rapper announced the arrival of her daughter Kali Love on March 15. 

The former Bachelor contestant and  San Francisco 49ers linebacker welcomed their first baby, a son named Beau Anthony, on March 7. 

The couple announced the news on Instagram March 11, and noted in the caption that it was the “best day of our lives.”

Princess Diana's niece celebrated Mother's Day in the U.K. by sharing she and her husband privately welcomed their first baby.

“It’s the joy of my life to be your mummy, little one. I love you unconditionally," she captioned her March 10 Instagram post. "Happy Mother’s Day to those who celebrate today."

Pitch Perfect star Adam Devine and wife Chloe Bridges shared that they welcomed their first baby, son Beau Devine, on Feb. 16.

The Wonder Woman star announced on March 6 that she and her husband had welcomed their fourth baby, a daughter named Ori. According to the actress, the name means "my light" in Hebrew.

TLC singer Rozonda "Chilli" Thomas is officially a grandmother after her son and wife welcomed their baby girl on March 2.

Ted Lasso's Brendan Hunt welcomed his second son with fianceé Shannon Nelson on March 1. The 51-year-old announced on Instagram, “Say hello to Archibald Felix Nelson Hunt (Archie will do), born Friday March 1st, coming in at 9+lbs. He’s in perfect health, and his weary hero of a mother is recovering peacefully."

On Feb. 29, the Dallas Cowboys quarterback Dak Prescott welcomed his first child, daughter MJ, with girlfriend Sarah Jane Ramos. 

On Feb. 27, the former Victoria's Secret Angel and Snap Inc. CEO announced the couple welcomed their third baby, a son named Pierre Kerr Spiegel.

On Feb. 23, Harry Styles' older sister announced she and her partner of nine years, Michal Mylnowski, had welcomed a baby girl. The 33-year-old wrote on Instagram, "Took some time off to ensure the safe arrival of our baby girl, who is adored by her whole family."

Two years after the death of their son Elliot, the Siesta Key star and husband Ismael "Ish" Soto welcomed baby girl Sunday Christina Soto.

Their second son, Boone Joseph Russell, arrived on Feb. 13, with mom noting he came "a week before his due date. 8 pounds 3 oz of heaven. Hearts overflowing."

On Feb. 9, the retired NFL star and country singer welcomed their fourth baby together, a son named Denver Calloway Decker. As she shared on Instagram a week later, "Our beautiful boy is here."

In his first interview in years, The Big Bang Theory actor revealed to Architectural Digest he’s now married and that he and his wife welcomed baby girl Oona Evelena.

The Bachelor Nation alum and his fiancée welcomed baby girl River Rose Viall Feb. 2: "Named after Natalie's great grandmother and niece…the best part of life starts now."

The Big Brother alum gave birth to twin girls Sage Martin Murphy and Sela James Murphy in January, she exclusively told E! News. 

"Since my wife, Jamie and the girls took my last name, we wanted to honor Jamie's full birth name in both of their names," Christie explained. "'James' after Jamie and 'Martin' after her maiden name. It feels special and right!"

Two years after the death of his baby girl, The Challenge alum welcomed a son with a friend he had been romantically involved with.

"Aliyas Diamond Cain - 16.01.24, 4:32am, 9lbs 3oz," he wrote. "I will love you, appreciate you, guide you and protect you with all of my heart, for the rest of my life. & you will have the most beautiful guardian angel heaven holds watching over you and protecting you too." 

The Bachelor alum welcomed her third baby, her first with her husband, in late January.

"She's finally here," she wrote on Instagram at the time, noting they named the little one Rosie. "1.24.24 at 1:40pm in room 42."

Their baby girl joins big sisters Kinsley, 11, and Charlie, 10, who Amanda shares with ex-husband Nick Buonfiglio.

Nico Michael Phelps entered the world on Jan. 16, joining his three older brothers Boomer, 7, Beckett, 5, and Maverick, 4.

The Teen Mom 2 star officially became a mom of seven after she welcomed a baby boy and a baby girl with boyfriend Elijah Scott in January.

The YouTube couple welcomed a baby boy in January.

"our little guy arrived last week and everyone is happy and healthy," they wrote on Instagram Jan. 21. "we feel like the luckiest people in the world. we love you, Otis."

Alongside a black-and-white photo of their baby's feet, the actor and former Miss World America winner announced the arrival of their first baby together, Shepherd Lawrence Duhamel.

Josh is also dad to son Axl, born in 2013, with ex Fergie.

"Our worlds have been forever changed," the couple wrote on Instagram Jan. 10, announcing the arrival of their daughter Ella Reine Palmer. "Our hearts are overflowing with love and gratitude."

The Bachelorette alum and her husband welcomed a baby girl via surrogate, Clare announced Jan. 15.

The Luxembourg royal family welcomed their third child on Jan. 7, a baby boy named Balthasar Felix Karl. “He weighs 3,220 kg [7.1 lbs.] and measures 50 cm,” or 7 lbs, 1 oz. and 19.7 inches," a birth annoucement note. “Prince Balthazar and Princess Claire are in perfect health."

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