Kourtney Kardashian's son Reign Disick is a rock star! Credit: Gabriel Olsen/FilmMagic

So cute! Kourtney Kardashian shared a gorgeous Instagram photo on Thursday, Dec. 3, which showed her 11-month-old son, Reign Disick, strumming a guitar while wearing a tiny Yeezus T-shirt.

The sweet little boy looks mesmerized by the adult-sized instrument in the adorable photograph, and is seen plucking at the strings with his little chubby hands.

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A photo posted by Kourtney Kardashian (@kourtneykardash) on

And the youngster totally looks too cool for school in his mini-Yeezus T-shirt (thanks, Uncle Kanye West!), his stonewashed jeans, and his mini black boots.

Kardashian, who didn't caption the photo, has had her kids firmly on her mind in the past weeks as she's been working hard on her relationship with ex Scott Disick, allowing him to step back into their lives after his stint in rehab.

“She has 100 percent let him back in her life and family life,” an insider told Us earlier this week, of the 36-year-old mom of three. “She’s committed to reintegrating him into the kids’ lives.”

The Keeping Up With the Kardashians star has made this decision because Disick is sober now, the source says of the troubled star, who checked into Cliffside Malibu for alcohol and substance abuse in early October.

“Kourtney is proud of the progress Scott has made since he’s left rehab,” another source previously told Us.

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