AceShowbiz - Kim Kardashian is seemingly involved in another sibling rivalry. If a new report is to be believed, there's tension between the SKIMS founder and sister Kylie Jenner that will spiral out of control.

Kim reportedly was livid at mom Kris Jenner for letting Kylie keep her romance with Timothee Chalamet secret. It was said that the former wife of Kanye West hinted at her feelings when she referred to Kylie as "private little soul" in the caption of her birthday tribute for the latter.

"They've tried to put differences aside, but things keep coming up," an insider told In Touch. "Kim really resents that Kylie gets away with keeping her personal life private and still manages to stay in their mom's good graces. Kylie has a different set of rules, and Kim feels it's really unfair."

Not stopping there, Kim was reportedly not happy when the Kylie Cosmetics founder became the first in the family to land on the highly coveted British Vogue cover for the September issue. "Kim can't stand that Kylie got the cover when she never did. She's very jealous," the source added.

The report additionally claimed that Kim feels that Kylie doesn't appreciate the sacrifices she's made for the family. "Kylie is very entitled about it all," said the insider. "It drives Kim up the wall that Kylie never really credits her for opening every door for her."

Meanwhile, the source also talked about Kylie's alleged obsession with age. Of the Khy founder, who landed in hot water for saying that 28-year-old Kendall Jenner was "basically 30," the informant claimed, "Kylie is obsessed with age and being the youngest in the family and always puts her sisters down for being older. In fact, she doesn't shy away from telling people Kim should start acting her age. It's just so rude."