Rumer Willis is already treating her baby to the finest of fabrics.

The pregnant “House Bunny” actress — who’s expecting her first child with boyfriend Derek Richard Thomas — is teaming up with Naked Cashmere on a Mother’s Day collection, and posed nude for a campaign announcing the partnership.

In one sultry shot, 34-year-old Willis shows off her baby bump in the buff, covering her body with various knit styles from the brand.

In another, she poses pantsless in a slouchy Naked Cashmere sweater with a soft blanket wrapped around her waist.

And in a third campaign image, Willis wears a knit pant and open cardigan from the label, the latter styled sans shirt.

Per the brand’s press release, the star’s collaboration with Naked Cashmere will be ongoing; she’ll be “curating capsule collections for mothers and newborns and collaborating on future styles.”

Her first will feature cashmere styles “reimagined for the modern woman and mom,” and include “versatile and stylish pieces that provide comfort and ease during and post pregnancy.”

Willis confirmed her relationship with Thomas, a musician, in November. And last month, the couple celebrated with a baby shower that boasted a star-studded guest list.

Among Willis’ attendees were mom Demi Moore, stepmother Emma Heming, influencer Stephanie Shepherd and “Dancing With the Stars” alum Peta Murgatroyd.

Thomas even wooed guests by playing the piano at the event, though the mom-to-be’s father, Bruce Willis, was unable to attend due to his worsening dementia.

Shortly after, however, Rumer celebrated the “Die Hard” actor’s birthday by posting a video showing off her bump in a blue dress and hugging her dad alongside her family.

Moore will surely be sporting her eldest daughter’s cashmere designs as she becomes a grandmother for the first time.

The “Ghost” actress, 60, shared photos of Willis’ pregnancy announcement with the caption, “Entering my hot kooky unhinged grandma era.”