Tyga and Kylie Jenner celebrated the New Year together as the pair vacationed with a few of their friends in Mammoth Lakes, California.

According to E! Online, the couple's holiday appearance marked the first time that the two were seen together in almost a month after a short breakup last year, which reportedly took place before Tyga's birthday. While the two looked happy during their vacation, there are reports that the couple has hit a rough patch in their relationship as there are claims that the rapper cheated on the reality star.

According to Us Weekly, Tyga reportedly cheated on the 18-year-old with Brazilian model Annalu Cardoso. A source told the website that the rapper met the 23-year-old model on one of his video shoots and she later appeared on his MTV2 reality show, "Kingin' with Tyga." The rapper is said to have set his sights on Cardoso but made sure that his girlfriend did not know about it.

"Tyga is very careful and waits until Kylie is out of the country," the source told Us Weekly.

The insider said that Tyga and Cardoso began texting around December 2014, months after he threw Kylie a party for her 17th birthday.

The source said that Tyga would text the model how he was doing and then he would ask her to send pictures and to meet up. The insider added that Tyga has also introduced Cardoso to some of his friends.

"She and Tyga wouldn't be extremely affectionate in front of them, but she could tell his friends all knew that they were something," said the source.

The source also said that the rapper would never talk about the "Keeping Up with the Kardashians" star when the model was around, and for her part, Cardoso reportedly also did not ask about them "because he was acting like someone who didn't have a girlfriend."

A second source told the website that Tyga panicked when it appeared that his relationship with the model might go public and that Cardoso has stopped talking to him.

Tyga has yet to respond to the report.