Kendall & Kylie Jenner at WAR over Tyga!

At first glance Kylie Jenner ’s family seemed more than happy about her romance with 26-year-old rapper Tyga .

But as the months roll on and the cracks appear to show in the couple’s relationship, reports that family member are concerned have started to emerge.

Yesterday it was reported that Kim and momager Kris have considered getting a private investigator to follow Tyga to prevent him planning anything – like eloping with her.

And now it’s been claimed that Kendall is just as unhappy about her little sister’s relationship.

In fact things are so bad the pair became embroiled in a huge row at the American Music Awards, according to Heat magazine.

Model Kendall was reportedly left fuming when she realised that Kylie had taken Tyga back after he was reportedly caught flirting with models while the sisters were away working .

According to reports things came to a head when they went back to their room to change before the AMA’s after party.

A source told the magazine: “Kendall was telling Tyga that if he really cared for Kylie, he’d treat her beter. Kylie defended him and they ended up in a big row.”

Kendall wasn’t seen after the incident while Kylie and Tyga went on to party.

“Kendall can’t stand how Tyga treats Kylie. Kendall thinks Tyga spends Kylie’s money, doesn’t pay her enough attention and there are always rumours about other women calling him. But when she tries to talk to Kylie about it, it always ends in a screaming row,” the source revealed.

The pair are known for having huge rows in the past – most recently on an episode of the show when they fought over dresses.