Kourtney Kardashian ponders why her sisters, Kim and Khloe Kardashian, are single.

According to a source close to the eldest Kar-Jenner sister, there is a reason why her sister's dating relationships aren't prospering and ending happily ever after, unlike hers.

The 43-year-old "The Kardashians" actress recently revealed to her followers that she has begun to appreciate her curvier physique while dating her now-husband Travis Barker.

However, a source told The Sun that Kim and Khloe had gone too far with their slender bodies.

The 41-year-old mother of four and the 38-year-old mother of two have both shed a significant amount of weight in recent years.

Kim has shed more than 20 pounds since the beginning of the summer, but Khloe has lost 60 pounds in the previous four years.

According to a source close to Kourtney, she warns against going near her two sisters in the middle of the day since they are both so hungry that they snap at just about anyone.

Kourtney is also certain that that is the reason her sisters are still single.

"Because no guy can stand their rigid daily schedules and twice-day exercises."

Kim Kardashian has previously boasted about her 5 a.m. gym fitness routine, while Khloe has published pictures showing off her skinnier stomach while working out.

Per the insider, neither the SKIMS creator nor the Good American founder ever have fun since they are so concerned with calories.

"[Kourtney] believes it is impossible to be in a joyful relationship like that ever again."

Meanwhile, Kourtney has been gushing about how thrilled she is with her weight since since she had extensive IVF treatments to become pregnant.

According to her anonymous pal, she understood that eating the odd treat won't hurt after hooking up with the Blink 182 drummer.

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Kourtney Kardashian Is Finally Content with Her Body

While appearing for Bustle magazine, Kourtney Kardashian discussed her good body image.

The Poosh founder said on the current episode of "The Kardashians" that she felt embarrassed after gaining weightwhile having IVF.

Kourtney informed her assistant and stylist on the set of the shoot that the treatment had taken a toll on her physically and psychologically, but that it had made her feel comfortable and content with the changes.

She also talked about Travis Barker's encouragement of her positive attitude about her physique.

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