Model Kendall Jenner says having older siblings make you mature quickly and admits she grew up too fast.

The "Keeping Up with the Kardashians" star has penned a column for Wall Street Journal magazine's February issue. The 19-year-old model, who was named as one of 25 most influential teens in 2014, shared her opinion about the topic of youth, reports aceshowbizz.com.

"I feel like I grew up too fast a long time ago. Having older siblings, you grow up around adults, so you mature more quickly. I saw my sisters and parents working every day, so I was pretty much brought up to be a workaholic. But I just turned 19 a couple weeks ago, and I'm scared to be 20-it's the first step out of being a teenager," the model shared.

"My sister Khloe always says to me and my younger sister, Kylie: 'You have your whole life to be an adult but only so long to be a kid.' And we get it. In the right situations, I try to be as immature as I can sometimes-react to things as if I were 12. You can't take things too seriously," the Estee Lauder spokesmodel added.

Kendall found it funny to think about her father Bruce Jenner as a teen.

"I just laugh thinking about my dad being a teenager, partying. It's the funniest thing. And it makes me think, 'What am I going to be like when I'm 65?'," she said.