Kim Kardashian asks her sister Kourtney for parenting advice

Kourtney told the October issue of Natural Health magazine: "[My kids] love [North] so much. I'm so happy that Penelope gets to grow up with a cousin close to her age, too.

"They're less than a year apart. Kim asks me for advice a lot, but she's such a great mom, very nurturing. It's nice to see how people [parent] differently.

"Our kids are all lucky to have many different people around them to give them so much love."

Meanwhile, Kourtney - who is pregnant with her third child - insists she was forced to learn the importance of healthy eating when she first fell pregnant in 2009.

She explained: "I was not raised this way--people just weren't as aware of healthy eating as they are today. When I got home from school, my snack was a bag of chips or cookies, and as an adult, I didn't even know what organic meant--I'd just go to the market and buy the same things my mom bought. I didn't really have any thoughts about it before I had my kids.

"Starting off, I was big on breastfeeding; I nursed my first for 14 months and my second for 16. That was important to me. Then I began making their baby food myself, all of it organic. After that, I was super cautious about what to introduce into their diets."