Happy birthday to you! Rob Kardashian celebrated his 29th birthday with a day of low-key, down-to-earth celebrations, courtesy of his girlfriend, Blac Chyna.

The 27-year-old model documented parts of her boyfriend's big day on Thursday, March 17, via Snapchat, revealing to fans that his birthday morning began with breakfast in bed (consisting mainly of protein, with sausage, bacon and eggs on the plate, and just one mini croissant).

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A photo posted by Rob K Snapchats (@robphuckedme) on

Once the couple had gotten up, they hit the shops together, and judging by Kardashian's cheeky video, a rear-view image of his girlfriend's curves was all he really needed to feel in the birthday mood.

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"Happy birthday to me," he sang happily as he videoed Chyna's booty from behind as she walked through a store. The video, initially zoomed in on her butt, slowly pans out to reveal her face and a cute hairband she’s wearing with shamrocks on it, to celebrate St. Patrick's day.

After the shopping trip, the couple hit the nail spa, where they sipped on mimosas and indulged in a little birthday pampering.

And later that evening, it was time for cake! Excited mom Kris Jenner sent her son a cute birthday gateau, iced with a pair of socks, in honor of his Arthur George line ("Thanks MAMA" the appreciative son wrote as he Snapchatted a picture of the creation).

But it was girlfriend Chyna's cake that was eventually used for Kardashian's modest birthday gathering that evening, when candles were lit and his closest pals sang him a rousing rendition of "Happy Birthday." (The video didn't show whether any of his famous family members were present at the intimate party, but they all wished him happy birthday earlier in the day via social media.)

While Kardashian's birthday celebrations were quiet compared with those of some of his more exuberant siblings, there's no doubt this birthday boy is finally happy.

“They’re really super silly, and they love each other," Chyna's pal Amber Rose told Us Weekly earlier this month of the happy couple. "They have a blast together."

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