Lionel and Nicole Richie Say Sofia Is 'Bumping Along' as Pregnancy Due Date Nears (Exclusive)

Lionel Richie and Nicole Richie are ready for their family's new addition to make their arrival! The father-daughter duo spoke with ET's Cassie DiLaura at the premiere of Nicole's new film, Don't Tell Mom the Babysitter's Dead, where they shared their excitement over Sofia Richie's pregnancy journey as her due date draws closer.

The expectant mom, 25, and her music executive husband, Elliot Grainge, 30, have been sharing the special milestones of her pregnancy on social media. In January, the couple took to TikToK to share the private reveal of their baby's sex they pulled off. In the video, Sofia is seen standing in their backyard as Elliot holds a confetti cannon with their dog watching astutely. The model and influencer, clearly giddy and impatient, counts down from three until her husband pulls the trigger and pink powder and confetti fills the air. 

Richie -- who is the daughter of music icon Lionel Richie and fashion designer Diane Alexander -- lets out a loud shriek after seeing the color symbolizing the baby is a girl and then runs around the backyard before falling to her knees.

"sorry to all my neighbors for the horrifying scream 😅," she wrote in the video's caption.

Lionel, who is already a grandfather to Nicole's 16-year-old daughter, Harlow, and her 14-year-old son, Sparrow, with husband Joel Madden, tells ET that he's more than excited to be "Pop-Pop" to Sofia's baby girl.

"[Sofia's] bumping along... right now we're just waiting for the baby to arrive," he shares of the model's current status. 

Despite it being a while since he's had to deal with diapers, Lionel says he's ready to tackle diaper duty when it comes! 

"They're going to accuse me of being too rough. No, it's called, 'I know how to handle the situation,'" the American Idol judge declared. "Pop-pop is ready, make no mistake."

As for Nicole, who walked the red carpet with her husband and kids, she can barely contain her elation over her sister's impending due date. 

"I'm beside myself, I don't even know what to say," the mom of two tells ET. "I have to like, really contain all of my excitement." 

The imminent arrival of Sofia's baby girl isn't the only exciting family news for Nicole. Her brother and sister-in-law, Joel's twin brother, Benji Madden, and his wife, Cameron Diaz, recently announced that they welcomed their second child — a son named Cardinal. 

When asked whether Benji spoke to Joel about choosing a bird name for his son, Nicole tells ET, "I didn't ask, but I really don't think they did. I think it's just a twin thing -- who knows?" 

Nicole adds that "everyone's amazing" amidst the new addition.

ET also spoke with Joel on the red carpet at AMC The Grove in Los Angeles about his nephew's name. 

"It was a surprise to all of us. We're all very happy though," Joel tells ET. 

Cameron and Benji announced the birth of their son, Cardinal, in March. 

"We are blessed and excited to announce the birth of our Son, Cardinal Madden❤️🙏He is awesome and We are all so happy he is here!" the couple wrote on Instagram. "For the kids safety and privacy we won’t be posting any pictures- but he’s a really cute ☺️We are feeling so blessed and grateful 🍀."

Cardinal joins big sister, Raddix, 4. 

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