Brody Jenner shared that he's "counting down the days" until he's an uncle, alongside a cute photo of him rubbing pregnant Leah Jenner's baby bump. Credit: Courtesy of Leah Jenner/Instagram

Somebody is going to be the cool uncle! Brody Jenner shared his excitement about becoming a future uncle in a sweet Instagram post featuring his pregnant sister-in-law Leah and big brother Brandon on Wednesday, June 24.

"Uncle Brody is counting down the days!!!!!" the former Hills heartthrob, 31, wrote, alongside a photo of his hand nestled lightly atop Leah's ever-growing bump. Meanwhile, future dad Brandon gives his wife's stomach a firm grasp as the trio looks delighted as they anticipate the eventual addition to their brood.

This will be the first child for Leah, 32, and Brandon, 34, who revealed the sex of their baby earlier this month. “So excited to meet our little girl," Don Felder's daughter captioned a romantic snap of herself holding a large pink rose while her husband kisses her from behind.

Leah, who's luckily experienced a beautiful pregnancy, recently spoke to Us Weekly about how excited she is for motherhood. "I feel honored to have this little life growing inside me," she told Us. "And I'm amazed by the power of the female body."

Her bachelor brother-in-law, meanwhile, has made no hints about settling down. Brody gave a no-holds-barred interview to GQ earlier this month about all things sex. "I'd have to say [the best sex I’ve ever had is] with my girlfriend, Kaitlynn [Carter],” Kim Kardashian’s stepbrother noted. "We have the best sex together, but we also switch it up and do fun things as well. We're not opposed to having somebody else join in on our sexcapades."

In fact, Carter herself is also open to the possibility of a threesome. "I truly believe that a lot more people are a lot more receptive than you think," the Sex With Brody star told the mag. “And when the conversation was brought up, Kaitlynn said, ‘I actually don't mind that at all.' So I was extremely excited about that."

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