Rob Kardashian celebrated his 29th birthday today (March 17) with a trip to LEGOLAND. His girlfriend Blac Chyna and her son King Cairo were also along for the fun.

TMZ captured photos of three celebrating Kardashian's big day. The whole situation seems extremely awkward though as King Cairo is the son of Tyga, who is currently dating Rob's sister Kylie Jenner. The former couple of Tyga and Blac Chyna getting into relationships with members of the Kardashian-Jenner family is certainly a headline-grabber.

Kanye West, who is also part of the Kardashian family through his marriage to Kim, even commented on the situation with a line on his new album, The Life of Pablo. "Blac Chyna fucking Rob, hope it help him with the weight," 'Ye raps on "Highlights."

Tyga and Blac Chyna have a rocky past to say the least. The two began dating in 2011, and had their son in 2012. They would break up in 2014, in a nasty split, which only got more contentious as Tyga began a controversial relationship with Kylie Jenner.

Blac Chyna would put Tyga on blast by tweeting screenshots of some affectionate text messages he sent to her. As their public spat continued through 2015, Tyga began taunting his ex. This would lead to more back and forth between the two.

It appears that things may have finally settled down though. When news of Blac Chyna and Rob Kardashian's relationship went public, Tyga was quite diplomatic about it.

"Everyone deserves to be happy," Tyga said in a statement to E! News.

Still, the next Kardashian family gathering might create a tremendous amount of awkwardness if everyone's significant others are in attendance.

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